Current status of the generation and transmission of the optical frequency standards

Anatoly S. Bashkin

The current status of quantum frequency standards is considered. A systematic comparison is made of the results achieved so far. The advantages and disadvantages of the principal types of microwave and optical quantum frequency standards are discussed. An analysis is given of the prospects of further progress which might result from improvements in the existing devices or from the development of new ones.

R. Ambartzymian, Nikolai G. Basov, P V Kryukov +1 more

Y. H. Wang, T. Liu, Alois Stejskal +7 more

We report on the current status of the optical frequency standard based on a single 115In+ ion. A single Indium ion is being trapped in a Paul-Strauble type trap and cooled in combination of Doppler cooling and sideband cooling to its lowest vibrational states. To interrogate the1S0-3P0clock transition with high accuracy we demonstrate a Hz-level laser system resonant to this transition. With the current setup we are able to achieve a measured linewidth of the clock transition of 260 Hz. The statistical uncertainty of the absolute frequency measurement is 3×10-13, limited mainly by our reference frequency standard.

Dwayne Knight, K. I. Pharaoh, S.L.T. Drysdale +3 more

Muhammad Usman, Simone Raponi, Marwa Qaraqe +1 more

The massive deployment of IoT devices being utilized by home automation, industrial and military scenarios demands for high security and privacy standards to be achieved through innovative solutions. This paper proposes KaFHCa, a crypto-less protocol that generates shared secret keys by combining random frequency hopping collisions and source indistinguishability independently of the radio channel status. While other solutions tie the secret bit rate generation to the current radio channel conditions, thus becoming unpractical in static environments, KaFHCa guarantees almost the same secret bit rate independently of the channel conditions. KaFHCa generates shared secrets through random collisions of the transmitter and the receiver in the radio spectrum, and leverages on the fading phenomena to achieve source indistinguishability, thus preventing unauthorized eavesdroppers from inferring the key. The proposed solution is (almost) independent of the adversary position, works under the conservative assumption of channel fading (σ=8dB), and is capable of generating a secret key of 128 bits with less than 564 transmissions.

D. J. E. Knight, K. I. Pharaoh, S.L.T. Drysdale +3 more