uantum-Atom Optics Laboratory

ห้องปฎิบัติการทัศนศาสตร์เชิงอะตอมควอนตัม

Cold and Ultra-cold Atom System

Since 2009, the Quantum-Atom Optics (QAO) Laboratory has established and been financially supported by the Thailand Center of Excellence in Physics (ThEP) to construct a system capable of producing cold (<150µK) neutral rubidium atoms. The project was initially meant to realize the Bose-Einstein condensate (BEC) and to make cold atoms accessible to multidisciplinary researchers. Over the years, we have built several highly-stable diode laser systems, set up standard frequencies using Doppler-free Saturated Absorption Spectroscopy (DSAS), and achieved the first magneto optical trap (MOT) of Thailand in July, 2011. Today, the MOT is routinely produced and our extended facility can conduct various standard cooling and trapping techniques that have been broadly employed in reputable laboratories worldwide.

Laser System

The mass production of laser diodes for electrical appliances has been continuously reducing the cost per piece while various customary operations additionally provide wide and selective ranges of wavelengths. A proportion of those intense light emitted are visible and may be tuned to resonance with the hyperfine splitting of alkali atoms. The low cost diode lasers have granted ample opportunities for experimental atomic physics for all countries in the world no matter what the pecuniary status. The QAO lab has been developing techniques for controlling Fabry-Perot diode lasers to a stability of one part per hundred billion as required for modern AMO science. Since six to ten lasers, all work in concert at slightly different wavelengths, are needed in a typical experiment; we are now endeavoring fully automated laser-controller system to bring out the capabilities and possibilities so that they can be managed single-handedly. With a tapered-chip amplifier integrated, our lasers will be non-compromising on power, line-width and stability.

Single Atom Trap

A system of just 30 cold neutral atoms among which the interactions can be coherently controlled would surpass the calculation power of the current fastest classical supercomputer. Its utmost computing speed will unprecedentedly accelerate methodological advances in all disciplines and inevitably introduce to technological revolution. To exploit the power of quantum computing, deterministic preparation of single atoms in a fiducial state is a crucial step. For that, a novel versatile focused-beam trap (FBT) is being implemented in our lab. When fully manipulated, the system can be scaled up to trapping in 3D optical lattices, one of the most promising candidates that play an important role in neutral-atom-based quantum logic devices and quantum memory. The picture shows our simulation of what might be realized in a few months.

Rydberg Atoms

Frontier physics studied in extreme conditions, i.e. near ionization state, sub-microkelvin regime and ultrahigh precision measurements, has not only bridged up astrophysics and AMO physics but also led to an unparalleled collaboration known as experimental astrophysics for the first time in ASEAN. Research project partnership between the two organizations, i.e. the National Astronomical Research Institute of Thailand (Public Organization) (NARIT) and the Department of Physics and Material Science, Chiang Mai University, implements a novel plan of action that will grant astrophysicists an accessible pathway to interstellar gases in a controllable earthbound laboratory. When successfully produced, the spectroscopic information therein will be studied and remodeled accordingly to show the evidence of the former existence of Rydberg spectrum lines. Tracing for the carriers of the undisclosed interstellar diffusion bands using strong Stark Effect is also made possible. Not to mention that Rydberg atoms are an essential ingredient to sensitivity in quantum non-demolition measurements that caught the eyes of the 2012 Nobel prize committee, Thailand will be among a few countries in the world that can produce and utilize them in an unprecedented aspect.

Atom Chip

We aim to collapse bulky cooling and trapping devices to fit most crucial parts in a volume not greater than 8cm3. Single atoms produced are floating on a tiny silicon wafer within magneto-optical confinement, which will serve as a prototype for a portable atom chip. The chip is wholly enclosed in a vacuum glass cube with no electrical lead and can be magnetically & optically controlled. The idea is that one can carry this cube anywhere, insert it into any trapping machine and have a personal single atom trap in less than a second. “Ambitious achievement?” let’s recall the first 5 minutes of the film “Artificial Intelligence” backs in 2001, that is how it works.

Quantum Simulations

Controlling an ensemble of particles at the quantum scale is a strenuous effort for physicists. For decades to come, it will also be a driving force to the ultimate goal for engineering. The study of an exotic and fragile many-body system requires an analogue controllable assemblage with identical and definite Hamiltonian. Within this scenario, we are using our cold atom facility, basically the optical lattices that provide nearly unlimited ways to imitate solid state systems, to flexibly control the electronic, translation and vibration states with tunable interactions. Questions that are not traceable using classical computation or unreachable in-vivo may be addressed. Our current research involves experimental verification of the simplest model for correlated composite particles, i.e. the Bose-Hubbard model. Soon with our expected powerful tapered lasers, we will be able to produce tight and periodic optical confinement for the quantum simulation of spin frustrating systems.