EDUCATION
RESEARCH INTERESTS
Quantum optics with superconducting circuits
Superconducting circuits cooled down to millikelvin temperatures can be designed to emulate the behaviour of natural atoms. This makes it possible to study quantum optics, the interaction between light and matter at the level of single photons and atoms, in regimes that are hard to reach in natural systems. The artificial atoms formed by the superconducting circuits, also called superconducting quantum bits (qubits), are a promising platform for implementing quantum information processing (quantum computation and quantum simulation). My main research interest is to explore the new regimes of quantum optics that can be reached with superconducting artificial atoms.
2010 - 2014
Chalmers University of Technology
Ph.D. in theoretical physics, working on quantum optics with superconducting circuits.
Supervisor: Professor Göran Johansson.
Ultrastrong light-matter coupling
In the last few years, experiments in several solid-state systems, in particular in superconducting circuits, have managed to reach the regime of ultrastrong coupling between light and matter. In this regime, the strength of the coupling between atoms and photons becomes comparable to the bare transition frequencies in the system. This ultrastrong coupling gives rise to many new and interesting phenomena. My research in this field is mostly about using higher-order processes enabled by the ultrastrong coupling to realize nonlinear-optics-like processes for single photons and many-body interactions for qubits.
Quantum acoustics
Superconducting artificial atoms are usually coupled to photons at microwave frequencies, but recent experiments have shown that they can also be made to interact with surface acoustic waves (SAWs), which are mechanical vibrations propagating on the surface of a piezoelectric substrate. Since the SAW quanta are phonons, this can be called quantum acoustics instead of quantum optics. The SAW phonons propagate much slower than, and have much shorter wavelength than, microwave photons. I study the physics that arises in this new regime, where, e.g., the artificial atom can be much larger than the wavelength of the phonons it interacts with, something which usually does not occur in conventional quantum optics.
2006 - 2010
Chalmers University of Technology
M.Sc. in Engineering Physics (Master programme: Nanoscale Science and Technology).
OTHER INTERESTS
Chess
I have played chess since I was seven years old. I am currently a FIDE master (FM) with an Elo rating of 2329, representing Örgryte Chess Club, Asaka Chess Club, and Tokyo Bilingual Chess Club. I enjoy teaching chess to children both in Sweden and Japan. Ten of my students have become national champions in their age groups.
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Climbing
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Quantum machine learning
Both machine learning and quantum physics have attracted a lot of interest in recent years, so the question has naturally been asked whether advantages can be gained by combining the two fields. I look at both quantum versions of neural networks and at how machine-learning methods can help us characterize quantum systems. I find the latter the most promising direction at the moment, e.g., using machine-learning methods to help with quantum state or process tomography.