Charged quantum dot micropillar system for deterministic light-matter interactions

Abstract

Quantum dots (QDs) are semiconductor nanostructures in which a three-dimensional potential trap produces an electronic quantum confinement, thus mimicking the behavior of single atomic dipole-like transitions. However, unlike atoms, QDs can be incorporated into solid-state photonic devices such as cavities or waveguides that enhance the light-matter interaction. A near unit efficiency light-matter interaction is essential for deterministic, scalable quantum-information (QI) devices. In this limit, a single photon input into the device will undergo a large rotation of the polarization of the light field due to the strong interaction with the QD. In this paper we measure a macroscopic (∼6• ) phase shift of light as a result of the interaction with a negatively charged QD coupled to a low-quality-factor (Q ∼ 290) pillar microcavity. This unexpectedly large rotation angle demonstrates that this simple low-Q-factor design would enable near-deterministic light-matter interactions. DOI: 10.1103/PhysRevB.93.241409 The deterministic, lossless exchange of energy between charged QDs and single photons has been shown as the potential building block for a full range of components required for QI and quantum communication [1][2][3]. A deterministic light-matter interaction would give one the ability to both switch the photon state with a high fidelity as well as keep photon loss near zero (high efficiency). To achieve these simultaneously, it is essential that all the photon energy that couples to and from the quantum emitter must do so almost exclusively within a well-defined electromagnetic mode, where one can input/collect single photons. Input/output coupling efficiency is parametrized by the β factor, the ratio between the rate of coupling of the dipole to this well-defined mode compared to the total coupling rate of the dipole to all available electromagnetic modes, including leaky ones.Great success has been had in approaching this limit in several systems, including photonic crystal (PC) waveguides [4] and photonic nanowires [5]. For optical cavities, however, this limit has proven difficult to approach. Light-matter interaction strengths in the "strong coupling" regime have been achieved for high-Q-factor pillar microcavities [6] and in photonic crystal cavities [7], and could show high fidelity switching. However, the input/output mode is usually not well defined in high-Q-factor cavities: the escape rate to and from a well-defined input channel is similar to the escape rate to leaky cavity modes (CMs). These leaky modes arise either from the intrinsic design of the structure or from fabrication imperfections, putting a limit on the efficiency of high-Qfactor microcavities where the escape rate into the input/output mode is slow by design. However, in a low-Q-factor pillar the cavity lifetime is very short. Thus one may easily design a high-β-factor structure with a well-defined input/output mode, a crucial advantage [8].The β factor is directly linked to the competition between the rates of coherent and incohere...

Tamm plasmons for efficient interaction of telecom wavelength photons and quantum dots

“…Hence, the wavelength and polarization resonance can be shaped using simple metal deposition techniques. This avoids the need to etch the QDcontaining layers, which is thought to lead to charge noise in the structure [15], [16]. CTPs have already been demonstrated in several QD-based applications such as lasers [17] and single-photon sources [18], [19] but to our knowledge have never been considered in the telecoms wavelength regime.…”

Polymer photonic microstructures for quantum applications and sensing

“…Further, we show how Purcell factors up to 4.5 with a total of 16 pairs of substrate and 15 top pairs distributed Bragg reflector can be achieved for wavelength scale hemispheres. With careful spectral and spetial mode engineering and colour centres with low phonon coupling, these structures may hold a key element to potential resonant scattering experiments (Noda et al 2007;Androvitsaneas et al 2016). We concluded with an experimental proposal for the realisation of the here simulated polymer structures.…”

Spin-based single-photon transistor, dynamic random access memory, diodes, and routers in semiconductors

“…• induced by a single hole spin [64] or electron spin [65]. However, these experiments were performed in weakly coupled cavity-QED systems [66][67][68] (similar to waveguide-QED structures [69,70]) with lower device performance, e.g., suffering from spectral diffusion of QD, low P max , low or no SPT gain, and vulnerable to quantum or classical fluctuations and electric/magnetic fields.…”