Shape-preserving and unidirectional frequency conversion by four-wave mixing

Abstract

In this work, we investigate the properties of four-wave mixing Bragg scattering driven by orthogonally polarized pumps in a birefringent waveguide. This configuration enables a large signal conversion bandwidth, and allows strongly unidirectional frequency conversion as undesired Bragg-scattering processes are suppressed by waveguide birefringence. Moreover, we show that this form of Bragg scattering preserves the (arbitrary) signal pulse shape, even when driven by pulsed pumps.

Group-velocity symmetry for highly adaptable quantum frequency conversion

“…For example, if the source wavelength were to change, phase mismatch would accrue and, even if one pump field were tuned to maintain energy conservation, conversion efficiency would drop rapidly and a new device with a different dispersion profile would be required. Typical conversion bandwidths are on the order of a few nanometers [34], though we note that work has been done to engineer larger conversion bandwidths in the 10-100 nm range both in BS-FWM conversion [35,36] as well as Raman-mediated frequency conversion in atomic ensembles [37].…”

Toward a Quantum Memory in a Fiber Cavity Controlled by Intracavity Frequency Translation

“…We fabricated a fiber cavity in a polarizationmaintaining (PM) fiber (Fibercore HB800). Birefringent PM fiber has been shown to offer the possibility of efficient, unidirectional frequency translation by BSFWM, with favorable phase-matching conditions for broadband signal pulses [34]. Phase matching is achieved for unidirectional frequency translation with the control pulses launched on the two orthogonal polarization axes.…”

“…Phase matching is achieved for unidirectional frequency translation with the control pulses launched on the two orthogonal polarization axes. In a fiber with normal dispersion, for appropriate control frequency separation the signal is frequency down-shifted by BSFWM when launched on the fast (-) axis, according to ω r = ω s − (ω q − ω p ), where ω i = 2πc /λi [34]. Figure 2(a) and inset (b) show the coating transmission T measured on a blank substrate during the coating run (Omega Optical).…”

Observation of Rapid Adiabatic Passage in Optical Four-Wave Mixing

“…Open to platforms suitable for low intensity fields such as the highly nonlinear fiber platform used here and potentially on-chip silicon waveguides [16], AFWM might be used for the processing of photonic qubits over wide bandwidths. Also open to high-flux platforms such as gas-filled fibers, AFWM might be used for the control of strong-field and attosecond domain light-matter interactions [17][18][19][20][21][22], the spectroscopy of ultrafast photo-induced molecular dynamics [23], laser-based particle acceleration [24], all-optical signal processing [25,26], and up-conversion imaging [27].…”

“…An adiabatic BS FWM process could be used for precise and uniform control of the photon splitting ratio over greatly widened bandwidths and potentially used in low-loss allfiber or on-chip platforms. As shown, the adiabatic phase matching approach also allows a broad conversion bandwidth for spectral regions separated by multiple octaves, and overcomes the traditional restriction of working at wavelength ranges with low dispersion for broadband wave mixing in either BS FWM or degenerate-pumped FWM applications, such as close to a zero-dispersionwavelength [4,7,25]. For high-intensity, ultrashort pulse applications, the weak dispersion of gas phase media in hollow core fibers could allow multiple octaves of conversion bandwidth while accommodating multi-mJ pulse energies.…”