Ultra Fast Nonlinear Optical Tuning of Photonic Crystal Cavities

We demonstrate fast (up to 20 GHz), low power (5 $\mu W$) modulation of photonic crystal (PC) cavities in GaAs containing InAs quantum dots. Rapid modulation through blue-shifting of the cavity resonance is achieved via free carrier injection by an above-band picosecond laser pulse. Slow tuning by several linewidths due to laser-induced heating is also demonstrated

Local On-Chip Temperature Tuning of InGaAs Quantum Dots

Quantum network based on InGaAs quantum dots (QDs) rely on QDs being in resonance with each other. We developed a new technique based on temperature tuning to spectrally align QDs located on the same chip

An optical modulator based on a single strongly coupled quantum dot - cavity system in a p-i-n junction

We demonstrate an optical modulator based on a single quantum dot strongly coupled to a photonic crystal cavity. A vertical p-i-n junction is used to tune the quantum dot and thereby modulate the cavity transmission, with a measured instrument-limited response time of 13 ns. A modulator based on a single quantum dot promises operation at high bandwidth and low power

Local Quantum Dot Tuning on Photonic Crystal Chips

Quantum networks based on InGaAs quantum dots embedded in photonic crystal devices rely on QDs being in resonance with each other and with the cavities they are embedded in. We developed a new technique based on temperature tuning to spectrally align different quantum dots located on the same chip. The technique allows for up to 1.8nm reversible on-chip quantum dot tuning

Linewidth broadening of a quantum dot coupled to an off-resonant cavity

We study the coupling between a photonic crystal cavity and an off-resonant quantum dot under resonant excitation of the cavity or the quantum dot. Linewidths of the quantum dot and the cavity as a function of the excitation laser power are measured. We show that the linewidth of the quantum dot, measured by observing the cavity emission, is significantly broadened compared to the theoretical estimate. This indicates additional incoherent coupling between the quantum dot and the cavity.Comment: 5 pages, 4 figure

Resonant Excitation of a Quantum Dot Strongly Coupled to a Photonic Crystal Nanocavity

We describe the resonant excitation of a single quantum dot that is strongly coupled to a photonic crystal nanocavity. The cavity represents a spectral window for resonantly probing the optical transitions of the quantum dot. We observe narrow absorption lines attributed to the single and biexcition quantum dot transitions and measure antibunched population of the detuned cavity mode [g^(2)(0)=0.19]

Optical manipulation of quantum dot excitons strongly coupled to photonic crystal cavities

In this paper, we review some recent cavity quantum electrodynamic (CQED) experiments with single quantum dot exciton coupled to photonic crystal cavities, performed in our group. We show how the coupled quantum-dot/cavity system can be used to modulate light with at a very fundamental level with very low power and discuss some applications of these low power modulators

Quantum and classical information processing with a single quantum dot in photonic crystal cavity

The experiments show that the coupled QD-cavity system is a promising candidate for probing CQED as well as for optical information processing. Our present work includes building of a three level system in a QD coupled to cavity, which is essential for construction of any quantum information processing devices

Independent electrical tuning of separated quantum dots in coupled photonic crystal cavities

Systems of photonic crystal cavities coupled to quantum dots are a promising architecture for quantum networking and quantum simulators. The ability to independently tune the frequencies of laterally separated quantum dots is a crucial component of such a scheme. Here, we demonstrate independent tuning of laterally separated quantum dots in photonic crystal cavities coupled by in-plane waveguides by implanting lines of protons which serve to electrically isolate different sections of a diode structure.Comment: 3 pages, 3 figure