Template:Publications Highlight
In this work we study theoretically the joint spectral properties of photon-pairs produced through spontaneous four-wave mixing (SFWM) with two spectrally distinct pump pulses in optical fibers. We show that, due to the group velocity difference between the pulses, the signature of the interaction can be significantly different from spontaneous parametric down-conversion or SFWM with a single pump pulse.
This work studied the generation of picosecond acoustic pulses generated by ultrafast optical excitation of a photo-acoustic transducer using time-resolved x-ray diffraction. The resulting pump-probe spectra reveal that the spatiotemporal structure of the acoustic pulse is bipolar with acoustic wavevectors up to inverse of the film thickness.
Spins confined in quantum dots are a leading candidate for solid-state quantum bits that can be coherently controlled by optical pulses. The use of hole spins allows the suppression of decoherence via hyperfine interactions and enables coherent spin rotations using Raman transitions mediated by a hole-spin-mixed optically excited state. Because the spin mixing is present only in the optically excited state, dephasing and decoherence are strongly suppressed in the ground states that define the qubits and nondestructive readout is possible. We present the qubit and device designs and analyze the wavelength tunability and fidelity of gate operations that can be implemented using this strategy. We then present experimental and theoretical progress toward implementing this design.