Setting a disordered password on a photonic memory
  Encryption is a vital tool of information technology protecting our data in the world with ubiquitous computers. While photons are regarded as ideal information carriers, it is a must to implement such data protection on all-optical storage. However, the intrinsic risk of data breaches in existing schemes of photonic memory was never addressed. We theoretically demonstrate the first protocol using spatially disordered laser fields to encrypt data stored on an optical memory, namely, encrypted photonic memory. Compare with a digital key, a continuous disorder encrypts stored light pulses with a rather long key length against brute-force attacks. To address the broadband storage, we also investigate a novel scheme of disordered echo memory with a high fidelity approaching unity. Our results pave novel ways to encrypt different schemes of photonic memory based on quantum optics and raise the security level of photonic information technology. 
Shih-Wei Su, Shih-Chuan Gou, Lock Yue Chew, Yu-Yen Chang, Ite A. Yu,   Alexey Kalachev and Wen-Te Liao
quant-ph physics.atom-ph