Atomic nucleus excited with laser: a breakthrough after decades
https://www.sciencedaily.com/releases/2024/04/240429103045.htm
The 'thorium transition', which has been sought after for decades,
has now been excited for the first time with lasers.
This paves the way for revolutionary high precision technologies, including nuclear clocks
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
 https://www.sciencedaily.com/releases/2024/04/240429103045.htm
  The 'thorium transition', which has been sought after for decades,
  has now been excited for the first time with lasers.
  This paves the way for revolutionary high precision technologies,
including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
https://www.sciencedaily.com/releases/2024/04/240429103045.htm
The 'thorium transition', which has been sought after for decades,
has now been excited for the first time with lasers.
This paves the way for revolutionary high precision technologies, including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
On Tue, 7 May 2024 14:35:12 +0100, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
https://www.sciencedaily.com/releases/2024/04/240429103045.htm
The 'thorium transition', which has been sought after for decades,
has now been excited for the first time with lasers.
This paves the way for revolutionary high precision technologies, including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
"the correct energy of the thorium transition was hit exactly, the
thorium nuclei delivered a clear signal for the first time. "
I wonder what that signal was.
On Tue, 7 May 2024 14:35:12 +0100, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
https://www.sciencedaily.com/releases/2024/04/240429103045.htm
The 'thorium transition', which has been sought after for decades,
has now been excited for the first time with lasers.
This paves the way for revolutionary high precision technologies, including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
"the correct energy of the thorium transition was hit exactly, the
thorium nuclei delivered a clear signal for the first time. "
I wonder what that signal was.
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
<https://www.sciencedaily.com/releases/2024/04/240429103045.htm>
The 'thorium transition', which has been sought after for decades,
has now been excited for the first time with lasers.
This paves the way for revolutionary high precision technologies,
including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
<https://www.sciencedaily.com/releases/2024/04/240429103045.htm>
The 'thorium transition', which has been sought after for decades,
has now been excited for the first time with lasers.
This paves the way for revolutionary high precision technologies,
including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to >electromagnetic radiation. This will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net> wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman <jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
 <https://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>   The 'thorium transition', which has been sought after for decades, >>>>>   has now been excited for the first time with lasers.
  This paves the way for revolutionary high precision technologies, >>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to
electromagnetic radiation. This will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
They aren't tuning to a resonance, but to the difference between two
close resonances.
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
 <https://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>   The 'thorium transition', which has been sought after for decades, >>>>>   has now been excited for the first time with lasers.
  This paves the way for revolutionary high precision technologies, >>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to
electromagnetic radiation. This will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two
close resonances.
On 5/8/24 01:36, John Larkin wrote:
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
  <https://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>>    The 'thorium transition', which has been sought after for
decades,
   has now been excited for the first time with lasers.
   This paves the way for revolutionary high precision technologies, >>>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to
electromagnetic radiation. This will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two
close resonances.
The current definition of the second uses something similar: Some
hyperfine resonance of cesium. Normal resonances are in the optical
domain, but hyperfine ones are RF.
In nuclei, normal transitions are in the gamma domain, and
hyperfine ones are in the domain of optics. It's just a change
of scale, if you will.
On 08/05/2024 09:44, Jeroen Belleman wrote:
On 5/8/24 01:36, John Larkin wrote:
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
  <https://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>>>    The 'thorium transition', which has been sought after for >>>>>>> decades,
   has now been excited for the first time with lasers.
   This paves the way for revolutionary high precision
technologies,
including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to
electromagnetic radiation. This will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two
close resonances.
The current definition of the second uses something similar: Some
hyperfine resonance of cesium. Normal resonances are in the optical
domain, but hyperfine ones are RF.
Which puts them in the RF frequency domain where counting cycles of the continuous sine reference waveform is relatively easy.
Likewise for H-maser another favourite local time reference signal.
In nuclei, normal transitions are in the gamma domain, and
hyperfine ones are in the domain of optics. It's just a change
of scale, if you will.
Although there will be some big practical difficulties counting cycles
of a waveform at 8eV which is up into the UV. What is the current
highest frequency that a semiconductor divider is capable of accepting?
I know that there are some optical logic circuits about but how capable
are they at near UV light?
You can't mix this thing down without losing its fidelity. I know how to double optical frequencies but how do you halve or quarter them?
On 08/05/2024 09:44, Jeroen Belleman wrote:
On 5/8/24 01:36, John Larkin wrote:
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
<https://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>>> The 'thorium transition', which has been sought after for
decades,
has now been excited for the first time with lasers.
This paves the way for revolutionary high precision technologies, >>>>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to
electromagnetic radiation. This will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two
close resonances.
The current definition of the second uses something similar: Some
hyperfine resonance of cesium. Normal resonances are in the optical
domain, but hyperfine ones are RF.
Which puts them in the RF frequency domain where counting cycles of the >continuous sine reference waveform is relatively easy.
Likewise for H-maser another favourite local time reference signal.
In nuclei, normal transitions are in the gamma domain, and
hyperfine ones are in the domain of optics. It's just a change
of scale, if you will.
Although there will be some big practical difficulties counting cycles
of a waveform at 8eV which is up into the UV. What is the current
highest frequency that a semiconductor divider is capable of accepting?
I know that there are some optical logic circuits about but how capable
are they at near UV light?
You can't mix this thing down without losing its fidelity. I know how to >double optical frequencies but how do you halve or quarter them?
On 08/05/2024 09:44, Jeroen Belleman wrote:
On 5/8/24 01:36, John Larkin wrote:
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades
ÿÿ <https://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>>> ÿÿÿ The 'thorium transition', which has been sought after for
decades,
ÿÿÿ has now been excited for the first time with lasers.
ÿÿÿ This paves the way for revolutionary high precision technologies, >>>>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to
electromagnetic radiation.ÿ This will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two
close resonances.
The current definition of the second uses something similar: Some
hyperfine resonance of cesium. Normal resonances are in the optical
domain, but hyperfine ones are RF.
Which puts them in the RF frequency domain where counting cycles of the continuous sine reference waveform is relatively easy.
Likewise for H-maser another favourite local time reference signal.
In nuclei, normal transitions are in the gamma domain, and
hyperfine ones are in the domain of optics. It's just a change
of scale, if you will.
Although there will be some big practical difficulties counting cycles
of a waveform at 8eV which is up into the UV. What is the current
highest frequency that a semiconductor divider is capable of accepting?
I know that there are some optical logic circuits about but how capable
are they at near UV light?
You can't mix this thing down without losing its fidelity. I know how to double optical frequencies but how do you halve or quarter them?
Martin Brown <'''newspam'''@nonad.co.uk> wrote:
On 08/05/2024 09:44, Jeroen Belleman wrote:
On 5/8/24 01:36, John Larkin wrote:
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades >>>>>>>> ?tps://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>>>> ?e 'thorium transition', which has been sought after for
decades,
?s now been excited for the first time with lasers.
?is paves the way for revolutionary high precision technologies, >>>>>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to >>>>> electromagnetic radiation.? will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two
close resonances.
The current definition of the second uses something similar: Some
hyperfine resonance of cesium. Normal resonances are in the optical
domain, but hyperfine ones are RF.
Which puts them in the RF frequency domain where counting cycles of the
continuous sine reference waveform is relatively easy.
Likewise for H-maser another favourite local time reference signal.
In nuclei, normal transitions are in the gamma domain, and
hyperfine ones are in the domain of optics. It's just a change
of scale, if you will.
Although there will be some big practical difficulties counting cycles
of a waveform at 8eV which is up into the UV. What is the current
highest frequency that a semiconductor divider is capable of accepting?
I know that there are some optical logic circuits about but how capable
are they at near UV light?
You can't mix this thing down without losing its fidelity. I know how to
double optical frequencies but how do you halve or quarter them?
You mix with an optical frequency comb, possibly with an intermediate
locking step.
The cleverest part of the Hall-Haensch comb generator is that you can lock >the blue end of the comb to the second harmonic of the red end, one tooth >off, and lock the difference to a good reference. Then all the teeth have
the same phase noise as the reference oscillator, rather than 20 log(600
THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
That 0.002 Hz line width is going to make the locker design entertaining.
That 0.002 Hz line width is going to make the locker design entertaining.
Yes, it will be combs and etalons.
I'm waiting for a flood on the Time Nuts reflector.
Joe Gwinn
Martin Brown <'''newspam'''@nonad.co.uk> wrote:
On 08/05/2024 09:44, Jeroen Belleman wrote:
On 5/8/24 01:36, John Larkin wrote:
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades >>>>>>>> ?tps://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>>>> ?e 'thorium transition', which has been sought after for
decades,
?s now been excited for the first time with lasers.
?is paves the way for revolutionary high precision technologies, >>>>>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious.
No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to >>>>> electromagnetic radiation.? will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two
close resonances.
The current definition of the second uses something similar: Some
hyperfine resonance of cesium. Normal resonances are in the optical
domain, but hyperfine ones are RF.
Which puts them in the RF frequency domain where counting cycles of the
continuous sine reference waveform is relatively easy.
Likewise for H-maser another favourite local time reference signal.
In nuclei, normal transitions are in the gamma domain, and
hyperfine ones are in the domain of optics. It's just a change
of scale, if you will.
Although there will be some big practical difficulties counting cycles
of a waveform at 8eV which is up into the UV. What is the current
highest frequency that a semiconductor divider is capable of accepting?
I know that there are some optical logic circuits about but how capable
are they at near UV light?
You can't mix this thing down without losing its fidelity. I know how to
double optical frequencies but how do you halve or quarter them?
You mix with an optical frequency comb, possibly with an intermediate
locking step.
The cleverest part of the Hall-Haensch comb generator is that you can lock >the blue end of the comb to the second harmonic of the red end, one tooth >off, and lock the difference to a good reference. Then all the teeth have
the same phase noise as the reference oscillator, rather than 20 log(600
THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
That 0.002 Hz line width is going to make the locker design entertaining.
Cheers
Phil Hobbs
On Wed, 8 May 2024 14:45:42 -0000 (UTC), Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:
Martin Brown <'''newspam'''@nonad.co.uk> wrote:
On 08/05/2024 09:44, Jeroen Belleman wrote:
On 5/8/24 01:36, John Larkin wrote:
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net> >>>>> wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades >>>>>>>>> ?tps://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>>>>> ?e 'thorium transition', which has been sought after for
decades,
?s now been excited for the first time with lasers.
?is paves the way for revolutionary high precision technologies, >>>>>>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious. >>>>>>> No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to >>>>>> electromagnetic radiation.? will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two >>>>> close resonances.
The current definition of the second uses something similar: Some
hyperfine resonance of cesium. Normal resonances are in the optical
domain, but hyperfine ones are RF.
Which puts them in the RF frequency domain where counting cycles of the
continuous sine reference waveform is relatively easy.
Likewise for H-maser another favourite local time reference signal.
In nuclei, normal transitions are in the gamma domain, and
hyperfine ones are in the domain of optics. It's just a change
of scale, if you will.
Although there will be some big practical difficulties counting cycles
of a waveform at 8eV which is up into the UV. What is the current
highest frequency that a semiconductor divider is capable of accepting?
I know that there are some optical logic circuits about but how capable
are they at near UV light?
You can't mix this thing down without losing its fidelity. I know how to >>> double optical frequencies but how do you halve or quarter them?
You mix with an optical frequency comb, possibly with an intermediate
locking step.
The cleverest part of the Hall-Haensch comb generator is that you can lock >> the blue end of the comb to the second harmonic of the red end, one tooth
off, and lock the difference to a good reference. Then all the teeth have
the same phase noise as the reference oscillator, rather than 20 log(600
THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
That 0.002 Hz line width is going to make the locker design entertaining.
Cheers
Phil Hobbs
Is there any way to divide a lightwave down into the electronic
frequency domain?
The cleverest part of the Hall-Haensch comb generator is that you can lock >the blue end of the comb to the second harmonic of the red end, one tooth >off, and lock the difference to a good reference. Then all the teeth have
the same phase noise as the reference oscillator, rather than 20 log(600
THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
On Wed, 8 May 2024 14:45:42 -0000 (UTC), Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:
Martin Brown <'''newspam'''@nonad.co.uk> wrote:
On 08/05/2024 09:44, Jeroen Belleman wrote:
On 5/8/24 01:36, John Larkin wrote:
On Tue, 07 May 2024 12:17:24 -0400, Joe Gwinn <joegwinn@comcast.net> >>>>> wrote:
On Tue, 7 May 2024 16:26:27 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 5/7/24 15:35, Martin Brown wrote:
On 07/05/2024 06:06, Jan Panteltje wrote:
Atomic nucleus excited with laser: a breakthrough after decades >>>>>>>>> ?tps://www.sciencedaily.com/releases/2024/04/240429103045.htm> >>>>>>>>> ?e 'thorium transition', which has been sought after for
decades,
?s now been excited for the first time with lasers.
?is paves the way for revolutionary high precision technologies, >>>>>>>>> including nuclear clocks
I wonder what the Q value for stimulated nuclear emission is?
They state a centre frequency of roughly 2 PHz and a decay time
of 630s, which would put the Q in the 1e19 ballpark. Prodigious. >>>>>>> No wonder it was hard to find.
The Time guys have been looking for this forever, so to speak.
It's the only atomic kernel transition with any degree of coupling to >>>>>> electromagnetic radiation.? will be orders of magnitude better
than such as lattice clocks.
There will be a flood of papers.
Joe Gwinn
They aren't tuning to a resonance, but to the difference between two >>>>> close resonances.
The current definition of the second uses something similar: Some
hyperfine resonance of cesium. Normal resonances are in the optical
domain, but hyperfine ones are RF.
Which puts them in the RF frequency domain where counting cycles of the
continuous sine reference waveform is relatively easy.
Likewise for H-maser another favourite local time reference signal.
In nuclei, normal transitions are in the gamma domain, and
hyperfine ones are in the domain of optics. It's just a change
of scale, if you will.
Although there will be some big practical difficulties counting cycles
of a waveform at 8eV which is up into the UV. What is the current
highest frequency that a semiconductor divider is capable of accepting?
I know that there are some optical logic circuits about but how capable
are they at near UV light?
You can't mix this thing down without losing its fidelity. I know how to >>> double optical frequencies but how do you halve or quarter them?
You mix with an optical frequency comb, possibly with an intermediate
locking step.
The cleverest part of the Hall-Haensch comb generator is that you can lock >> the blue end of the comb to the second harmonic of the red end, one tooth
off, and lock the difference to a good reference. Then all the teeth have
the same phase noise as the reference oscillator, rather than 20 log(600
THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
That 0.002 Hz line width is going to make the locker design entertaining.
Cheers
Phil Hobbs
Is there any way to divide a lightwave down into the electronic
frequency domain?
Rubidium clocks use an indirect way that doesn't actually divide.
On Wed, 8 May 2024 14:45:42 -0000 (UTC), Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:
[snip]
The cleverest part of the Hall-Haensch comb generator is that you can lock >> the blue end of the comb to the second harmonic of the red end, one tooth
off, and lock the difference to a good reference. Then all the teeth have
the same phase noise as the reference oscillator, rather than 20 log(600
THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
Hmm. It had to be true, but I never connected the dots there. What
is mechanism by which this is achieved? References?
Thanks,
Joe Gwinn
Joe Gwinn <joegwinn@comcast.net> wrote:
On Wed, 8 May 2024 14:45:42 -0000 (UTC), Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:
[snip]
The cleverest part of the Hall-Haensch comb generator is that you can lock >>> the blue end of the comb to the second harmonic of the red end, one tooth >>> off, and lock the difference to a good reference. Then all the teeth have >>> the same phase noise as the reference oscillator, rather than 20 log(600 >>> THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
Hmm. It had to be true, but I never connected the dots there. What
is mechanism by which this is achieved? References?
Thanks,
Joe Gwinn
Don’t have the reference handy, but the basic idea is to use a modelocked >system Ti:sapphire laser at 750 nm to generate ~100-fs pulses, then use >fiber/grating pulse compression to bring that down to a few femtoseconds, >followed by a holey fiber to broaden the spectrum to more than an octave.
Jan Hall is one of the best instruments guys ever.
On Wed, 8 May 2024 23:35:19 -0000 (UTC), Phil Hobbs ><pcdhSpamMeSenseless@electrooptical.net> wrote:
Joe Gwinn <joegwinn@comcast.net> wrote:
On Wed, 8 May 2024 14:45:42 -0000 (UTC), Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:
[snip]
The cleverest part of the Hall-Haensch comb generator is that you can lock >>>> the blue end of the comb to the second harmonic of the red end, one tooth >>>> off, and lock the difference to a good reference. Then all the teeth have >>>> the same phase noise as the reference oscillator, rather than 20 log(600 >>>> THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
Hmm. It had to be true, but I never connected the dots there. What
is mechanism by which this is achieved? References?
Thanks,
Joe Gwinn
Don’t have the reference handy, but the basic idea is to use a modelocked >>system Ti:sapphire laser at 750 nm to generate ~100-fs pulses, then use >>fiber/grating pulse compression to bring that down to a few femtoseconds, >>followed by a holey fiber to broaden the spectrum to more than an octave.
Jan Hall is one of the best instruments guys ever.
I'll poke around his publications. He's bound to have left tracks.
On Wed, 8 May 2024 23:35:19 -0000 (UTC), Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:
Joe Gwinn <joegwinn@comcast.net> wrote:
On Wed, 8 May 2024 14:45:42 -0000 (UTC), Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:
[snip]
The cleverest part of the Hall-Haensch comb generator is that you can lock >>>> the blue end of the comb to the second harmonic of the red end, one tooth >>>> off, and lock the difference to a good reference. Then all the teeth have >>>> the same phase noise as the reference oscillator, rather than 20 log(600 >>>> THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
Hmm. It had to be true, but I never connected the dots there. What
is mechanism by which this is achieved? References?
Thanks,
Joe Gwinn
DonÂ’t have the reference handy, but the basic idea is to use a modelocked >> system Ti:sapphire laser at 750 nm to generate ~100-fs pulses, then use
fiber/grating pulse compression to bring that down to a few femtoseconds,
followed by a holey fiber to broaden the spectrum to more than an octave.
Jan Hall is one of the best instruments guys ever.
I'll poke around his publications. He's bound to have left tracks.
Thanks,
Joe Gwinn
Joe Gwinn <joegwinn@comcast.net> wrote:
On Wed, 8 May 2024 23:35:19 -0000 (UTC), Phil HobbsHis given name is John L.
<pcdhSpamMeSenseless@electrooptical.net> wrote:
Joe Gwinn <joegwinn@comcast.net> wrote:
On Wed, 8 May 2024 14:45:42 -0000 (UTC), Phil HobbsDonÂ’t have the reference handy, but the basic idea is to use a
<pcdhSpamMeSenseless@electrooptical.net> wrote:
[snip]
The cleverest part of the Hall-Haensch comb generator is that you
can lock the blue end of the comb to the second harmonic of the red
end, one tooth off, and lock the difference to a good reference.
Then all the teeth have the same phase noise as the reference
oscillator, rather than 20 log(600 THz / 100 MHz) ~ 138 dB worse,
as it would be in a multiplier.
Hmm. It had to be true, but I never connected the dots there. What
is mechanism by which this is achieved? References?
Thanks,
Joe Gwinn
modelocked system Ti:sapphire laser at 750 nm to generate ~100-fs
pulses, then use fiber/grating pulse compression to bring that down to
a few femtoseconds, followed by a holey fiber to broaden the spectrum
to more than an octave.
Jan Hall is one of the best instruments guys ever.
I'll poke around his publications. He's bound to have left tracks.
Thanks,
Joe Gwinn
On Thu, 09 May 2024 14:26:12 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
On Wed, 8 May 2024 23:35:19 -0000 (UTC), Phil Hobbs >><pcdhSpamMeSenseless@electrooptical.net> wrote:
Joe Gwinn <joegwinn@comcast.net> wrote:
On Wed, 8 May 2024 14:45:42 -0000 (UTC), Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:
[snip]
The cleverest part of the Hall-Haensch comb generator is that you can lock
the blue end of the comb to the second harmonic of the red end, one tooth >>>>> off, and lock the difference to a good reference. Then all the teeth have >>>>> the same phase noise as the reference oscillator, rather than 20 log(600 >>>>> THz / 100 MHz) ~ 138 dB worse, as it would be in a multiplier.
Hmm. It had to be true, but I never connected the dots there. What
is mechanism by which this is achieved? References?
Thanks,
Joe Gwinn
Don’t have the reference handy, but the basic idea is to use a modelocked >>>system Ti:sapphire laser at 750 nm to generate ~100-fs pulses, then use >>>fiber/grating pulse compression to bring that down to a few femtoseconds, >>>followed by a holey fiber to broaden the spectrum to more than an octave. >>>
Jan Hall is one of the best instruments guys ever.
I'll poke around his publications. He's bound to have left tracks.
The best source I've found so far is:
Optical and microwave metrology with frequency combs
Tara Fortier
NIST Time and Frequency Division
Oct 10, 2023
And
COMMUNICATIONS PHYSICS | (2019)2:153 | >https://doi.org/10.1038/s42005-019-0249-y | www.nature.com/commsphys
These are open access.
Joe Gwinn
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