Coupling Quantum Tunneling with Cavity Photons

Abstract

Tunneling of electrons through a potential barrier is fundamental to chemical reactions, electronic transport in semiconductors and superconductors, magnetism, and devices such as terahertz oscillators. Whereas tunneling is typically controlled by electric fields, a completely different approach is to bind electrons into bosonic quasiparticles with a photonic component. Quasiparticles made of such light-matter microcavity polaritons have recently been demonstrated to Bose-condense into superfluids, whereas spatially separated Coulomb-bound electrons and holes possess strong dipole interactions. We use tunneling polaritons to connect these two realms, producing bosonic quasiparticles with static dipole moments. Our resulting three-state system yields dark polaritons analogous to those in atomic systems or optical waveguides, thereby offering new possibilities for electromagnetically induced transparency, room-temperature condensation, and adiabatic photon-to-electron transfer.

Tunable single-photon emission from dipolaritons

“…We consider a micropillar of 2 µm diameter with an embedded In 0.1 Ga 0.9 As/GaAs/In 0.08 Ga 0.92 As double quantum well, where each QW has 10 nm width and the spacer width is 4 nm [38]. The corresponding tunneling coupling and Rabi frequency of the exciton-photon coupling arehJ =hΩ = 6 meV.…”

“…1(a)]. The emergent dipolariton quasiparticles were shown to be useful for the generation of THz radiation [41,42,43] and enhancement of the nonlinear interparticle interaction due to its dipole-dipole nature [38]. Assuming low-intensity coherent pumping of the cavity mode, we perform master equation calculations and observe anti-bunching of photons originating from coherent coupling between the modes.…”

“…Here, we show that an unconventional photon blockade can be engineered in a dipolariton system [38,39], where direct exciton and indirect exciton [40] transitions of a double quantum well (QW) are strongly coupled to each other, and direct excitons are additionally strongly coupled to a cavity mode of a zero-dimensional micropillar [see sketch in Fig. 1(a)].…”

Continuous terahertz emission from dipolaritons

“…20 The DX-DX interaction constant can be estimated as V DD = 6E b a 2 B /S, 40 where the direct exciton Bohr radius and binding energy are a B = 10 nm and E b = 8 meV, respectively. Here S = 100 µm 2 is the laser excitation area.…”

“…17 This paper builds on the subject of a recent proposal to use a dipolariton system to generate pulses of THz radiation through oscillations in density between spatially direct and indirect excitons. 18 The dipolariton system consists of a semiconductor microcavity with a double quantum well (QW) embedded in the center 19,20 [see sketch in Fig. 1(a)].…”