Research Progress

Stimulated Raman adiabatic passage (STIRAP) allows efficiently transferring the populations between
wo discrete quantum states and has been used to prepare molecules in their rovibrational ground state. In

Measurement-device-independent quantum key distribution (MDI-QKD) can eliminate all detector side
channels and it is practical with current technology. Previous implementations of MDI-QKD all used two
symmetric channels with similar losses. However, the secret key rate is severely limited when different
channels have different losses. Here we report the results of the first high-rate MDI-QKD experiment over
asymmetric channels. By using the recent 7-intensity optimization approach, we demonstrate > 10 ×

Understanding quantum many-body systems with strong interactions and unconventional phases therein is one of the most challenging tasks in physics. In cold atom physics, this has been a focused research topic for nearly two decades, where strong interactions are naturally created and well manipulated by bringing the system close to a scattering resonance. However, most of the studies thus far have been limited to thes-wave resonance.

A quantum-dot-based device combines all of the attributes necessary for producing a reliable source of entangled photons for quantum information applications.

The new world record of 18-qubit quantum entanglement with six photons’ three degrees of freedom (6 × 3 = 18) has been achieved by USTC physicists PAN Jianwei (project leader), LU Chaoyang, LIU Naile, WANG Xilin et al., surpassing the previous world record of 10-qubit entanglement they made in 2016. The successful control over the high-dimensional entanglement is the key for speeding up quantum computing and the future quantum network. This breakthrough was published as the Editors’ Suggestion in the journal Physical Review Letters within only three weeks of submission.

Professor PAN Jianwei and Professor LU Chaoyang of the University of Science and Technology of China (USTC) carry out an experiment on boson sampling with photon loss in collaboration with Researcher YOU Lixing’s group of Shanghai Institute of Microsystem and Information Technology (SIMIT) of Chinese Academy of Sciences (CAS). The results show that boson sampling with a few photons lost can increase the sampling rate, which brings a demonstration of quantum supremacy closer to reality. This research is published in Physical Review Letters on June 6th as one of Editor’s Suggestions. The American Physical Society website Physics comments on the paper with a Viewpoint article entitled “Lost Photons Won’t Derail Quantum Sampling”.

"Beam me up, Scotty." The famous "Star Trek" catchphrase has launched teleporting daydreams the world over.

Now Chinese scientists have completed an experiment straight out of the realms of science fiction - quantum teleportation - from the ground to the world's first quantum satellite.

The experiment was similar in some ways to the Star Trek mode of transport, except that the scientists beamed up the quantum states of photons rather than people.

Four years ago, theoretical physicists proposed a new quantum-communication scheme with a striking feature: it did not require the transmission of any physical particles. The research raised eyebrows, but now a team of physicists in China claims it has demonstrated that the "counterfactual" scheme works. The group built an optical apparatus that it says can transfer a simple image while sending (almost) no photons in the process.

An entangled polarization state of ten photons sets a new record for multiphoton entanglement. Quantum computing requires multiple qubits entangled together. So far, only a handful of qubits have been coupled together successfully. A new experiment raises the bar with the entangling of ten photons, two more than the previous photon record. While still a ways off from what’s needed to make quantum computers competitive with classical ones, the entanglement of this many photons might be sufficient for certain quantum error correction codes and teleportation experiments.