Frequency cavity pulling induced by a single semiconductor quantum dot (original) (raw)

Cavity versus dot emission in strongly coupled quantum dots-cavity systems

2011

We discuss the spectral lineshapes of N quantum dots in strong coupling with the single mode of a microcavity. Nontrivial features are brought by detuning the emitters or probing the direct exciton emission spectrum. We describe dark states, quantum nonlinearities, emission dips and interferences and show how these various effects may coexist, giving rise to highly peculiar lineshapes.

Coherent excitation of a strongly coupled quantum dot - cavity system

2009

We have studied the coherent excitation of a strongly coupled QD/photonic crystal cavity system. Time-resolved reflectivity measurements show the vacuum Rabi oscillation of the dot in the cavity. Next, we considered the resonant driving of a cavity-detuned dot, which efficiently populates the cavity mode. This cavity-controlled read-out channel allows high-resolution single quantum dot spectroscopy. Autocorrelation measurements on the cavity mode show antibunching and suggest the use of the resonantly driven QD/cavity system as an on-demand source of single photons with potentially near-unity indistinguishability.

Cavity quantum electrodynamics with a single quantum dot coupled to a photonic molecule

Physical Review B, 2012

We demonstrate the effects of cavity quantum electrodynamics for a quantum dot coupled to a photonic molecule, consisting of a pair of coupled photonic crystal cavities. We show anti-crossing between the quantum dot and the two super-modes of the photonic molecule, signifying achievement of the strong coupling regime. From the anti-crossing data, we estimate the contributions of both mode-coupling and intrinsic detuning to the total detuning between the super-modes. Finally, we also show signatures of off-resonant cavity-cavity interaction in the photonic molecule.

Single-photon nonlinearity of a semiconductor quantum dot in a cavity

2006

A single atom in a cavity is the model system of cavity quantum electrodynamics (CQED). The strong coupling regime between the atom and cavity-confined photon corresponds to the reversible exchange of energy between the two modes, and underpins a wide range of CQED phenomena with applications in quantum information science, including for example as quantum logic gates and as sources of entangled states. 2,3,4 An important advance was achieved recently when strong coupling between excitons and cavity photons was reported for the first time for localized quantum dots (QDs) in micron-size solid state cavities, 5-8 . This has significance in terms of scalability and integration with other optical devices, and could lead to the emergence of 'quantum optics on a chip' technology. However the results presented so far for quantum dots are in the linear regime, corresponding to coupling to the vacuum field (vacuum Rabi splitting); they are not a true QED effect and can equally well be described by classical physics as the coupling between two oscillators. 9 In this paper, we present evidence for a purely quantum phenomenon for the QD/cavity photon system, namely the increase in splitting of the levels when the mean number of photons in the cavity is increased. This corresponds to non-linearities on the single-photon scale: the presence of a single excitation in the cavity changes the level structure, affecting the emission energies for a second photon. Such results are a first step in demonstrating the promise of quantum dots for CQED applications.

Non-resonant dot–cavity coupling and its potential for resonant single-quantum-dot spectroscopy

Nature Photonics, 2009

1 Promising solid-state single-photon sources and cavity quantum electrodynamic schemes have been realized on the basis of coupled quantum dot and micro-/nanocavity systems . Recent experimental studies on the single quantum dot (QD) level showed a pronounced emission at the cavity resonance even for strongly detuned dot-cavity systems 5]. This behaviour is indicative of a complex light-matter interaction in a semiconductor well beyond the widely used two-level emitter-cavity schemes. Different mechanisms such as photon-induced 'shake-up' processes in charged quantum dots , dephasing processes and phonon-mediated processes are currently discussed to understand the experimentally observed features. A well prepared and clearly defined experimental situation is therefore mandatory to gain a thorough understanding of the responsible physical mechanisms behind the non-resonant dot-cavity coupling.

Cavity quantum electrodynamics with semiconductor quantum dots

The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meeting, 2013

We describe a coherent control technique for coupling electron spin states associated with semiconductor double-dot molecule to a microwave stripline resonator on a chip. We identify a novel regime of operation in which strong interaction between a molecule and a resonator can be achieved with minimal decoherence, reaching the so-called strong coupling regime of cavity QED. We describe potential applications of such a system, including low-noise coherent electrical control, fast QND measurements of spin states, and long-range spin coupling.

Detuning effect in quantum dynamics of a strongly coupled single quantum dot–cavity system

Journal of Physics: Condensed Matter, 2008

The quantum dynamics of a strongly coupled single quantum dot-cavity system with non-zero detuning in a phonon bath is investigated theoretically in terms of a perturbation treatment based on a unitary transformation and an operator displacement. The decoherence due to phonons as a function of the detuning between the cavity mode and exciton is obtained analytically. It is shown that the detuning has a significant impact on the quantum dot exciton lifetime. In realistic experimental conditions, the calculated exciton lifetimes are in good agreement with recent experimental observation (Hennessy et al 2007 Nature 445 896).

Cavity-quantum electrodynamics with quantum dots

2003

Abstract Semiconductor quantum dots (QDs) have emerged as promising candidates for studying quantum optical phenomena. In particular, cavity-quantum electrodynamics effects can be investigated using a single QD embedded inside a photonic nanostructure, where both the carriers and photons are confined within sub-micron length scales in all three dimensions. Since QD location inside the cavity is fixed by the growth, this system is free of the stringent trapping requirements that limit its atomic counterpart.