High-harmonic probing of electronic coherence in dynamically aligned molecules

Abstract

We introduce and demonstrate a new approach to measuring coherent electron wave packets using high-harmonic spectroscopy. By preparing a molecule in a coherent superposition of electronic states, we show that electronic coherence opens previously unobserved high-harmonic-generation channels that connect distinct but coherently related electronic states. Performing the measurements in dynamically aligned nitric oxide (NO) molecules we observe the complex temporal evolution of the electronic coherence under coupling to nuclear motion. Choosing a weakly allowed transition to prepare the wave packet, we demonstrate an unprecedented sensitivity that arises from optical interference between coherent and incoherent pathways. This mechanism converts a 0.1 excitation fraction into a $\sim$20 signal modulation.

References in corpus (1)

• Coherent Electron Scattering Captured by an Attosecond Quantum Stroboscope

Cited by in corpus (13)

• Electronic decoherence following photoionization: full quantum-dynamical treatment of the influence of nuclear motion
• Decoherence and Revival in Attosecond Charge Migration Driven by Non-adiabatic Dynamics
• Can strong-field ionization prepare attosecond dynamics?
• Signatures of electronic structure in bi-circular high-harmonic spectroscopy
• Coherent electronic-vibrational dynamics in deuterium bromide probed via attosecond transient absorption spectroscopy
• Strong Field Ionization of Water II: Electronic and Nuclear Dynamics En Route to Double Ionization
• Towards complete all-optical emission control of high-harmonic generation from solids
• Coupled nuclear and electron dynamics in the vicinity of a conical intersection
• Attosecond XUV probing of vibronic quantum superpositions in Br${}_2^{+}$
• Characterizing Particle-Like Charge Migration Dynamics with High-Harmonic Sideband Spectroscopy
• Theoretical Study of Molecular Electronic and Rotational Coherences by High-Harmonic Generation
• Quantum-beat Auger spectroscopy
• Attosecond dynamics of light-induced resonant hole transfer in high-order-harmonic generation