RSS icon
Twitter icon
Facebook icon
Vimeo icon
YouTube icon

From a loophole-free Bell test to a quantum Internet

April 18, 2016 - 11:00am
Ron Hanson
QuTech and Kavli Institute of Nanoscience Delft
The realization of a highly connected network of qubit registers is a central challenge for quantum information processing and long-distance quantum communication. Diamond spins associated with NV centers are promising building blocks for such a network as they combine a coherent optical interface (similar to that of trapped atomic qubits) [1] with a local register of robust and well-controlled nuclear spin qubits [2]. We can now exploit these features simultaneously to achieve new functionalities such as unconditional remote quantum teleportation [3].
 Here we present our latest progress towards scalable quantum networks, including the first loophole-free violation of Bell’s inequalities [4]. Our Bell test is free of any experimental loopholes and thus directly tests the principles underlying the nature of reality. We create and exploit high-fidelity entanglement between diamond electron spins separated by more than 1 km, and combine this with efficient state detection to obtain a Bell violation.
 I will discuss how the techniques developed in these experiments may enable the realization of a network of quantum bit registers for quantum computation and communication. In the long run, such networks may lead to a quantum Internet secured through device-independent protocols – reaching the ultimate physical limits of privacy [5].
[1] H. Bernien et al., Nature 497, 86 (2013).
[2] T. H. Taminiau et al., Nature Comm (in press); arxiv:1508.01388.
[3] W. Pfaff et al., Science 345, 532 (2014).
[4] B. Hensen et al., Nature 526, 682 (2015).
[5] A. Ekert and R. Renner, Nature 507, 443 (2014).
CSS 2400
College Park, MD 20742

Subscribe to A Quantum Bit 

Quantum physics began with revolutionary discoveries in the early twentieth century and continues to be central in today’s physics research. Learn about quantum physics, bit by bit. From definitions to the latest research, this is your portal. Subscribe to receive regular emails from the quantum world. Previous Issues...

Sign Up Now

Sign up to receive A Quantum Bit in your email!

 Have an idea for A Quantum Bit? Submit your suggestions to