Space Quantum Communications paves the way to basic science, applications and cooperation

Speaker
Prof. Paolo Villoresi
Affiliation
Università degli Studi di Padova
Time
2019-07-05 (Fri) 10:00
Location
理化大楼一楼科技展厅(上海研究院4号楼329会议室同步视频)
Abstract

Quantum Communications are based on degrees of freedom (DoF) of light that allow for the sharing of
quantum states over long distances. The DoF for Space links are of interest to address the interplay of Quantum
Physics and Gravity as well as the applications as QKD on very long scales.
We shall describe some steps forward in the use of temporal modes for free-space Quantum Communications
(QC). These were initially used to investigate the superposition principle on a Space channel [1,2] and are
recently considered for an Optical Test of the Einstein Equivalence Principle [3].
A relevant development in the Lab use of the temporal modes includes the introduction of a scheme free from
the post-selection loophole, when entangled stated, that may be extended to free-space channels [4]. Moreover,
the experimental efforts to improve both the resolution in the temporal detection and the photon exchange scale
has now reached the level of 250 ps along a real space channel [5] and the altitude of 20000 km [6]
respectively, as well the Space extension of the John Wheeler wave-particle Gedankenexperiment [7].
The QC experiments along Space channels were realized at MLRO - Matera Laser Ranging Observatory of the
ASI Italian Space Agency, in Matera, Italy.

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