Resonator-assisted single molecule quantum state detection

Abstract

We propose a state-sensitive scheme to optically detect a single molecule without a closed transition, through strong coupling to a high-Q whispering-gallery mode high-Q resonator. A backgroundfree signal can be obtained by detecting a molecule-induced transparency in a photon bus waveguide that is critically coupled to the resonator, with a suppressed depumping rate to other molecular states by the cooperativity parameter C. We numerically calculate the dynamics of the molecule-resonator coupled system using Lindblad master equations, and develop analytical solutions through the evolution of quasi-steady states in the weak-driving regime. Using Rb2 triplet ground state molecules as an example, we show that high fidelity state readout can be achieved using realistic resonator parameters. We further discuss the case of multiple molecules collectively coupled to a resonator, demonstrating near-unity detection fidelity and negligible population loss.

Enriching the quantum toolbox of ultracold molecules with Rydberg atoms

“…Most molecules do not have a closed optical cycling transition, with the exception of a special set of molecules [3,28,29], making conventional fluorescence or absorption imaging techniques difficult for single-molecule detection [30]. A general route to overcoming such a challenge is to perform indirect detection through state-sensitive coupling of a molecule to another quantum system such as an atom [31][32][33][34][35] or optical cavity [36] which can then be optically detected.…”

Efficiently-coupled microring circuit for on-chip cavity QED with trapped atoms

“…Cold atoms trapped and interfaced with light in photonic optical circuits form exciting hybrid quantum platforms for quantum optics and atomic physics. Strong optical confinement in nanophotonic waveguides or resonators greatly enhances atom-light coupling beyond those achieved in diffraction-limited optics, enabling new opportunities in studying light-matter interactions [1][2][3][4][5][6][7][8] and radiative processes [9][10][11] . On the circuit-level, nanophotonic engineering offers a variety of tools in modifying the photonic density of states 12,13 , as well as controlling photon transport and device optical links [14][15][16][17][18] , thus enriching the complexity of atomphoton interactions and quantum functionality.…”

“…As a simple example, in Fig. 4 we plot a weakly-driven, steady-state bus waveguide transmission 11,39 , T (δ ) =…”