check
Condensed-Matter Seminar: "Quantum-logic precision spectroscopy and control of trapped molecules" | The Racah Institute of Physics

Condensed-Matter Seminar: "Quantum-logic precision spectroscopy and control of trapped molecules"

Date: 
Wed, 16/12/202010:00-11:30
Location: 
Virtual
Lecturer: 
Ziv Meir, University of Basel

Lecturer: Ziv Meir, University of Basel

Trapped ions are among the best-controlled quantum systems. However, for molecules, a
similar degree of control currently lacks due to their additional rotational and vibrational
degrees of freedom, severely complicating their energy-level structure. Quantum-logic
protocols in which atomic ions serve as probes for molecular ions promise quantumcontrol
over these degrees of freedom. Here, I will describe our experimental results in
achieving >99% fidelity in the quantum-nondemolition state detection of the nitrogen ion's
electronic, vibration, and rotation ground state [1], thus making a crucial step towards the
coherent manipulation of molecular quantum states. We further enhanced our quantumlogic
protocol for hyperfine and Zeeman resolved state identification and preparation in a
complex region of the molecular spectrum, mimicking the situation encountered with the
richer spectrum of polyatomic molecules [2].
The quantum control of rotation and vibration of molecules will improve precisionspectroscopy
of molecules by a few orders of magnitude. It will open up opportunities for
creating new time standards in the THz domain [3], testing beyond-standard-model
theories such as possible time variation in the proton-to-electron mass ratio, and encoding
quantum information in molecular qubits at telecom frequencies for quantumcommunication
applications. With the increasing size and complexity of the molecule
studied, it is an open question to what extent quantum control of these complex systems
can be maintained.
[1] Sinhal, ZM, Najafian, Hegi, Willitsch, Science 367, 1213 (2020).
[2] Najafian, ZM, Sinhal, Willitsch, Nat. Commun. 11, 4470 (2020).
[3] Najafian, ZM, Willitsch, Phys. Chem. 22, 23083 (2020).
[4] ZM, Hegi, Najafian, Sinhal, Willitsch, Faraday Discuss. 217, 561 (2019).