The Quantum Materials Lab is a part of Stewart Blusson Quantum Matter Institute at the University of British Columbia led by Andrea Damascelli. The main interest of the group focuses on studies of electronic properties of quantum materials (QM) – a broad range of compounds exhibiting exotic macroscopic properties which can only be explained in the framework of quantum mechanics – with angle-resolved photoemission spectroscopy (ARPES). One of our current research directions involve studies on the electronic structure of QM above the Fermi edge and its non-equilibrium dynamics with interferometric two-photon angle resolved photoemission (I2PPE ARPES). These investigations aim to gain insight into the relaxation of optically excited electrons through measuring the rate of elastic scattering and identify the scattering channels, and help to evaluate the feasibility of using these materials as base for future technological devices. The project will be led by Andrea Damascelli (supervisor) and Sergey Zhdanovich (co-supervisor).
The study involves a system of interest that is excited with a pair of identical ultrashort pulses separated by interferometrically stable time delay. The first pulse induces an oscillating polarization in the sample and the second pulse probes the polarization. If coherence in the system is preserved, the response of the system to this double pulse will depend on the relative phase of the pulses. If the second pulse is in phase with the first one, the amplitude of the oscillating polarization will increase. On the other hand, if the second pulse is out of phase the amplitude will completely vanish. If the system experiences decoherence during the time between the two pulses, the response will be independent of the pulses’ relative phase.
The student will participate in the preparation of, and conduct experiments which will include laser source diagnostics, modification, and alignment, sample preparation, characterization and data acquisition. The student will also analyze data as well as simulate the results of experiments using Matlab and Igor pro packages.
- Familiarization of the concepts of photoelectric effect and photoemission in solids (energy and momentum conservation laws)
- Familiarization with the technique of angular resolved photoelectron spectroscopy (density of states, material work function)
- Sample preparation for photoemission experiments
- Sample characterization using Laue diffraction
- Data analysis using IGOR, Matlab