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We propose a directionality orthogonal double-slit interferometry to control photoelectron dynamics in energy- and angle-resolved fashion. The two orthogonal components of polarization-skewed (PS) laser pulse, in which the total polarization vector rotates as time evolves, can be regarded as the double-slit in the time domain. Our results demonstrate that the peak splitting and shift in photoelectron momentum distributions can be controlled by the relative optical phase between two components of the PS pulse. Based on the analysis from time-dependent perturbation theory, the behaviors of photoelectrons in angle-integrated energy spectra between 1s and 2p initial states can be attributed to the significant discrepancy of an interference pattern, which is reflected in energy- and angle-dependent phase difference of transition amplitudes from two orthogonal components of PS pulse. In addition, the influences of time delay and intensity ratio between two subpulses on this coherent control are also discussed. Our work provides a feasible protocol for controlling photoelectron dynamics in energy and angular resolutions and enriches the potential applications of the double-slit interference in the time domain.

We study the ionization of atoms by very intense linearly polarized pulse with moderately high frequency by numerically solving the time-dependent Schrödinger equation (TDSE). In this regime, the photon energy exceeds the ionization potential allowing for one-photon ionization which is, however, strongly influenced by strong nonlinear photon-atom interactions. We find that the onset of atomic stabilization can be monitored by the appearance of a dynamic interference pattern in the photoelectron spectrum.

High angular momentum partial waves are indispensable in the numerical calculations of the time-dependent Schrödinger equation (TDSE) for the interaction between atoms and strong long-wavelength laser pulses. In these cases, the widely-applied Lanczos propagator, used to solve the TDSE, requires an extremely small time step to be convergent. By splitting out the centrifugal potential from the whole Hamiltonian, we demonstrate that the stiffness of the TDSE can be reduced and a rather large time step is allowed for the present Split-Lanczos propagator. Compared with the ordinary Lanczos propagator, the efficiency of the propagation can be improved by more than 100 times for large angular momentum in present tests.

Recent advance of lithium niobate microphotonic devices enables the exploration of intriguing nonlinear optical effects. We show complex nonlinear oscillation dynamics in high-Q lithium niobate microresonators that results from unique competition between the thermo-optic nonlinearity and the photorefractive effect, distinctive to other device systems and mechanisms ever reported. The observed phenomena are well described by our theory. This exploration helps understand the nonlinear optical behavior of high-Q lithium niobate microphotonic devices which would be crucial for future application of on-chip nonlinear lithium niobate photonics.

Integrated quantum photonics relies critically on the purity, scalability, integrability, and flexibility of a photon source to support diverse quantum functionalities on a single chip. Here we report a chip-scale photon-pair source on the silicon-on-insulator platform that utilizes dramatic cavity-enhanced four-wave mixing in a high-Q silicon microdisk resonator. The device is able to produce high-quality photon pairs at different wavelengths with a high spectral brightness of 6.24×10(7) pairs/s/mW(2)/GHz and photon-pair correlation with a coincidence-to-accidental ratio of 1386 ± 278 while pumped with a continuous-wave laser. The superior performance, together with the structural compactness and CMOS compatibility, opens up a great avenue towards quantum silicon photonics with capability of multi-channel parallel information processing for both integrated quantum computing and long-haul quantum communication.

We report the observation of optomechanical oscillation by immersing a silica microsphere in liquid. Due to the ultra high quality factor of the microsphere in the aqueous environment, sufficient optical force was established to quiver the microsphere at a pump laser power around 1 mW.

We propose and demonstrate compact suspended silicon microring resonators with ultra-high optical quality. We achieve an intrinsic quality factor of 9.2 × 10(5) for the resonator with a radius of 9 μm. The high optical quality factor, high optical confinement together with the suspended structure of our device enable great potential for broad applications in biosensing, quantum photonics, nonlinear photonics, cavity optomechanics, and optical signal processing.

We demonstrate a highly efficient optomechanical oscillator based upon a small silicon microdisk resonator with a 2-μm radius. The device exhibits a strong optomechanical coupling of 115 GHz/nm and a large intrinsic mechanical frequency-Q product of 4.32 × 10(12) Hz. It is able to operate at a high frequency of 1.294 GHz with an ultralow threshold of 3.56 μW while working in the air environment. The high efficiency, high frequency together with the structural compactness and CMOS compatibility of our device enables great potential for broad applications in photonic-phononic signal processing, sensing, and metrology.