Saturated absorption at nanowatt power levels using metastable xenon in a high-finesse optical cavity

Abstract

Strong saturated absorption at nanowatt power levels has been demonstrated using metastable xenon in a high finesse optical cavity. The use of metastable xenon allows a high quality factor of Q = 2 × 10(8) to be achieved at relatively high atomic densities without any contamination or damage to the optical surfaces, which is often a problem when using high-density rubidium or other alkali atoms. This technique provides a relatively straightforward way to produce nonlinearities at the single-photon level with possible applications in quantum communications and computing.

Cross-phase modulation enhancement via a resonating cavity: semiclassical description

“…This proposal satisfies the conditions necessary to realize optical quantum computation using weak nonlinearities as proposed by Munro, et al [30], non-local interferometry as proposed by Kirby and Franson [31,32], and device-independent quantum key distribution [33]. It also supports some recent experimental efforts [34][35][36].…”

Low-power cross-phase modulation in a metastable xenon-filled cavity for quantum-information applications

“…We previously demonstrated nonlinear saturated absorption at low power levels using metastable Xe in a resonant cavity [16]. The 4.5 fJ control pulses used in this experiment correspond to approximately 18,000 photons inside the cavity.…”

“…The resonant frequency of the cavity was tuned by varying the temperature of the mounting fixture as described in more detail in Ref. [16]. The RF discharge used to excite the Xe atoms into the metastable state produced no noticeable degradation of the cavity finesse.…”

Xenon-based Nonlinear Fabry-Perot Interferometer for Quantum Information Applications

“…Metastable xenon has optical properties similar to those of rubidium, but it does not degrade the sensitive cavity mirrors. The design of this system and some of its advantages have previously been discussed in a measurement of absorption saturation at nanowatt power levels [7]. Here we show evidence of the strong nonlinearity in an observation of self-phase modulation with an input power of a few tens of nanowatts [8].…”