Quantum optics or optical physics is the subfield of atomic, molecular, and optical physics that studies the generation of light, for example in the form of lasers or pulses of increasingly short durations, and the interaction of the generated light with matter. The development of ultrashort laser pulses allowed the study of processes that occur within the femtosecond (10-15 s) timescale, which correspond to the dynamics of charge carriers, atoms, and molecules as they rearrange to form new products in a chemical reaction. In addition, ultrashort pulsed light can also be used to create quasiparticles such as excitons and polaritons in order to observe and characterize their behavior.
Ultracold Atomic Physics
Light also exerts mechanical forces on matter in such a way that laser beams can be used to trap, stabilize, and manipulate atoms or ions individually in optical lattices. Light can also be used to cool atomic or molecular samples to near-zero temperatures via interactions with a laser field. In those systems, as the particles start to behave in a collective fashion, unique quantum phenomena such as superfluidity and superconductivity, phase transitions, and even new states of matter start to emerge. In addition, the properties of a well-understood and well-controlled system of ultracold atomic gases can be manipulated in such a way that the designed system directly resembles an unknown system one wishes to study. This approach is called quantum emulation or analogue quantum simulation and is another aspect of quantum computing and information processing. A quantum emulator is thus a fully-functional single-purpose quantum computer that can be used to study the many-body dynamics of strongly correlated quantum systems or out-of-equilibrium phenomena and properties.
The quantum properties of light are harnessed in the field of photonics, with a number of applications ranging from lightwave circuits, optical waveguides, fiber amplifiers, and micro-electro-mechanical systems. These devices are increasingly ubiquitous whether in medicine, telecommunications, or information processing. For example, light beams can be used to activate a switch by making use of the principles of nonlinear optics, i.e., the dependence of a medium’s coefficients on the incident light (intensity, polarization, wavelength). This application may hold the key to an optical computer in which all signals are carried by light instead of electrical signals.
At the Pittsburgh Quantum Institute
Research at the Pittsburgh Quantum Institute has yielded a number of exciting outcomes in the fields of optics and photonics, including flexible lightwave circuits in glass substrates, nonlinear optical topological insulators, and highly symmetrical and low-loss optical waveguides in flexible glass substrates that are thermally stable at high temperatures.
Spectroscopic techniques such as fluorescence spectroscopy, 2-dimensional-infrared spectroscopy, Raman spectroscopy, 2-photon photoemission spectroscopy are used to probe various systems ranging from ionic liquids to polymers to metal surfaces.
- Kevin Chen
- Ted Corcovilos
- Sean Garrett-Roe
- Hong Koo Kim
- Jennifer Laaser
- Jung-Kun Lee
- Linda Peteanu
- Hrvoje Petek
- David Snoke
- Elias Towe