Quantum bit string sealing

Though it was proven that secure quantum sealing of a single classical bit is impossible in principle, here we propose an unconditionally secure quantum sealing protocol which seals a classical bit string. Any reader can obtain each bit of the sealed string with an arbitrarily small error rate, while reading the string is detectable. The protocol is simple and easy to be implemented. The possibility of using this protocol to seal a single bit in practical is also discussed.Comment: Add a discussion on the possibility of sealing a single bit in practica

The Scientist, Fall 2008

https://scholarworks.sjsu.edu/scientist/1002/thumbnail.jp

The Feasibility of a Fully Miniaturized Magneto-Optical Trap for Portable Ultracold Quantum Technology

Experiments using laser cooled atoms and ions show real promise for practical applications in quantum- enhanced metrology, timing, navigation, and sensing as well as exotic roles in quantum computing, networking and simulation. The heart of many of these experiments has been translated to microfabricated platforms known as atom chips whose construction readily lend themselves to integration with larger systems and future mass production. To truly make the jump from laboratory demonstrations to practical, rugged devices, the complex surrounding infrastructure (including vacuum systems, optics, and lasers) also needs to be miniatur- ized and integrated. In this paper we explore the feasibility of applying this approach to the Magneto-Optical Trap; incorporating the vacuum system, atom source and optical geometry into a permanently sealed micro- litre system capable of maintaining $10^{-10}$ mbar for more than 1000 days of operation with passive pumping alone. We demonstrate such an engineering challenge is achievable using recent advances in semiconductor microfabrication techniques and materialsComment: 23 pages, 10 figure