Observing collisions beyond the secular approximation limit

Abstract

Energy transfer through quantum coherences plays an essential role in diverse natural phenomena and technological applications, such as human vision, light-harvesting complexes, quantum heat engines, and quantum information and computing. The understanding of the long-lived coherence involved in these phenomena requires a detailed modeling of the system-bath interactions beyond the so-called secular and/or Markovian approximations. Despite continuous theoretical progress on understanding nonsecular dynamics in the last decades, convincing experimental observations are still lacking. By using the laser-kicked molecular rotor as a model system, we here experimentally unveil the nonsecular dynamics in the rotational relaxation of molecules due to thermal collisions. Specifically, the rotational coherence in gas-phase molecules is systematically probed and characterized by the recently discovered rotational alignment echoes featuring a decoherence and dissipation process which can only be explained by the nonsecular quantum master equations for modeling molecular collisions.

References in corpus (6)

• Non-Markovian dynamics in open quantum systems
• Orientation and Alignment Echoes
• On the observation of field-free orientation of a symmetric top molecule by terahertz laser pulses at high temperature
• Echo Spectroscopy in multi-level quantum-mechanical rotors
• Coherent radiative decay of molecular rotations: a comparative study of terahertz-oriented versus optically aligned molecular ensembles
• Fractional Echoes

Cited by in corpus (7)

• Femtosecond rotational dynamics of D${}_2$ molecules in superfluid helium nanodroplets
• Echoes in Unidirectionally Rotating Molecules
• Molecular alignment echoes probe collision-induced rotational-speed changes
• Intrinsic Calibration of Molecular Alignment Using Rotational Echoes
• Echoes in a Single Quantum Kerr-nonlinear Oscillator
• Impulsively Excited Gravitational Quantum States: Echoes and Time-resolved Spectroscopy
• Lindblad parameters from high resolution spectroscopy to describe collision induced decoherence in the gas phase -- Application to acetylene