I am (a theoretician) looking for the experimental parameters where one can drive an optical cavity with maximum frequency. Interestingly, I am curious about the constrains so that one can't go beyond a limit of driven frequency.
Thanks...
Dear Vincent ,
When I say driving an optical cavity means driving optical mode/modes with a laser pump. I don't know, what else you can drive in a simple optical cavity ( Fabry-Perot Cavity).
Thanks. Ya I agree with you that I didn't mention about the optical cavity earlier. However, If the length of an optical cavity is getting changed, then I can't pump a single mode or modes inside the cavity with the same pump, as the displacement of the movable end mirror detunes the cavity modes, known as optomechanical cavity.
"scanning faster than the lifetime of photons", do you mean that to pump a cavity fast enough it should decay fast, right?.
I like @Vincent's answer! Must use it some lectures :)
As Vincent has answered, this is typically correct. Driving a cavity mode usually means that you are trying to couple into it, and so this introduces issues around the bandwidth of the excitation. Conventionally you would think of this as just the linewidth of the coupling, but of course an initial transient has to be finite width due to the time it takes to define a spectral feature. With this in mind you can see that to drive a cavity over short time scales (ie to make a fast modulation of the state of the cavity) typically requires a relatively poor cavity. So light storage time is essentially the inverse of speed.
Typically one might think, for example, of trying to change the properties of the cavity adiabatically.
There are, of course, interesting limits that go beyond such simple considerations.
There is a fascinating regime where you change the cavity properties on timescales very much shorter than the cavity lifetime to explore relativistic effects. A quick google turned up this rather nice thesis on superconducting relativistic cavity QED - Quantum optics and relativistic motion with superconducting circuits, Joel Lindkvist, http://publications.lib.chalmers.se/records/fulltext/226110/226110.pdf
that looks worth exploring further.
Vincent, Andrew: fascinating, I just wanted to add a couple of comments.
1. There is a regime where you "drive the cavity": scan the pump's frequency faster than a lifetime of a photon in a cavity. There are all kind of applications for this, especially, if you expect cavity properties to change due to external interactions. You can detect the PHASE shift between pump's and transmitted waves, to indicate the exact resonance, or resonance shft.
2. Couple of years ago, there has been a series of papers (cannot recall the authors by now) that introduced a strong kerr medium into a high Q cavity. The E-field inside cavity can be very high , (in fact, Q times stronger than pump's one), so kerr medium modified the effective length of the cavity, and kicked it out of resonance; obviously, field drops, and the cavity got back to resonance again... I believe authors have even showed some regime of bi -stability in the cavity with substantial hysteresis, it has been claimed applicable to data storage, but probably never got out of the lab.
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