Welcome to the Yan group homepage in Zhejiang University. Our group is in the School of Physics of ZJU.

Our address: No. 8, Haina Buliding , Zijingang Campus, Zhejiang University, Hangzhou, Zhejing, PRC.  

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Zeng Zixuan's paper got published in PRL, congratulations! 2024.10

Zixuan Zeng, Shuhua Deng, Shoukang Yang, and Bo Yan, Three-Dimensional Magneto-Optical Trapping of Barium Monofluoride. Phys. Rev. Lett. 133, 143404 (2024)

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Liang Qian's paper got online now, congratulations! 2024.09

Qian Liang, Zhaoli Dong, Jian-Song Pan, Hongru Wang, Hang Li, Zhaoju Yang, Wei Yi, Bo Yan, Chiral dynamics of ultracold atoms under a tunable SU(2) synthetic gauge field, Nature Physics (2024)

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Qian Liang got graduated, congratulations!  2024. 06

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Our new paper about time reflection is online now. Congratulations!

Quantum time reflection and refraction of ultracold atoms，

Zhaoli Dong, Hang Li, Tuo Wan, Qian Liang, Zhaoju Yang, Bo Yan 

Nature Photonics (2023). https://doi.org/10.1038/s41566-023-01290-1

A brief introduction in Chinese can be found 

Nature Photonics| 观察量子世界的时间反射和折射 (qq.com)

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We have moved our lab to the new campus-Zijingang Campus. 

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Our new posdoc Dr. Hang Li joined our group, welcome.

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Dizhou Xie got graduated, congratulations!  2021. 09

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Wenhao Bu got graduated, congratulations! 

2021.05.27

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Dr. Tao Chen's paper got published in npj Quantum information, Congratulations!

Quantum Zeno effects across a parity-time symmetry breaking transition in atomic momentum space, 

Tao Chen, Wei Gou, Dizhou Xie, Teng Xiao, Wei Yi, Jun Jing^#, and Bo Yan^#, 

npj Quantum Information 7,78 (2021)

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Dr. Wei Gou get graduated, Congratulations!!

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Our review paper got published in Physics.

颜波. 基于光晶格的超冷原子量子模拟[J]. 物理, 2021, 50(1): 31. Yan Bo. Quantum simulation based on ultracold atoms in a lattice. Physics, 2021, 50(1): 31.

Qian Liang's paper about SWAP cooling got published in Front. Phys., Congratulations!

Laser cooling with adiabatic passage for type-II transitions, Qian Liang, Tao Chen^#, Wen-Hao Bu, Yu-He Zhang, Bo Yan^#, Front. Phys. 16(3), 32501 (2021)

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Wei Gou (苟维) won  the 2019-2020 "National PHD scholarship" (国家奖学金（博士）)

Congratulations!

2020-10-19

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Dizhou Xie won  the 2018-2019 "National PHD scholarship" (国家奖学金（博士）)

Tengxiao won the 2020 "New PHD scholarship" of Zhejiang University (新生奖学金)

Congratulations!

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Our paper about disspative AB ring got published

Tunable Nonreciprocal Quantum Transport through a Dissipative Aharonov-Bohm Ring 

in Ultracold Atoms

Wei Gou*, Tao Chen*, Dizhou Xie, Teng Xiao, Tian-Shu Deng, Bryce Gadway, Wei Yi, and Bo Yan

Phys. Rev. Lett. 124, 070402 （2020）

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Our paper about quantum walk with BEC in the momentum space got published

Topological Quantum Walks in Momentum Space with a Bose-Einstein Condensate, 

Dizhou Xie* ,Tian-Shu Deng*, Teng Xiao, Wei Gou, Tao Chen, Wei Yi, and Bo Yan, 

Phys. Rev. Lett. 124, 050502 (2020)

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Our paper about the Type-II Zeeman slower got published.

Congradulation, Qian Liang.

Improvements on type-II Zeeman slowing of molecules through polarization selectivity, 

Qian Liang, Wenhao Bu, Yuhe Zhang, Tao Chen, and Bo Yan, 

Phys. Rev. A 100, 053402 (2019)

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Our paper of ultracold atoms got published.

Topological characterizations of an extended Su-Schrieffer-Heeger model,

Dizhou Xie, Wei Gou, Teng Xiao, Bryce Gadway and Bo Yan, 

npj Quantum Information, 5, 1 (2019)

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Our review paper of laser cooling of polar molecules got published (in Chinese)

陈涛, 颜波, 极性分子的激光冷却及囚禁技术, 物理学报, Acta  Phys.  Sin., 68, 043701(2019) 

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A new group photo. Happy new year!!!

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Dr. Tao Chen's paper about stimulated excitations of a driven BEC got published in PRA.

Congratulations!

Characterization of stimulated excitations in a driven Bose-Einstein condensate,

Tao Chen and Bo Yan, 

Phys. Rev. A 98, 061601 (2018)

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The joint start conference of the National Key R&D Program of China for our group and Porefessor

You's group in Tsinghua University hold in Beijing on Oct. 22, 2018.

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8 hour hiking (毅行) in 2018. Congratulations.

And welcome Xiao Teng (肖腾) and Zhang Yuhe (张宇和)。

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First Rb BEC in our group 2017.09.

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Our new results about BaF molecules got published.

Phys. Rev. A 96, 053401 (2017)

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A 6-hour hiring to celebrate our 120th anniversary of Zhejiang University.

2017/5/6

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Our first experimental paper of BaF molecules has been published.

Cold collision and high-resolution spectroscopy of buffer-gas-cooled BaF molecules, Wenhao Bu, Tao Chen, Guitao Lv, and Bo Yan, Phys. Rev. A 95, 032701 (2017).

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The theoretic paper about laser cooling of BaF was published.

Structure, branching ratios, and a laser-cooling scheme for the 138BaF molecule, Tao Chen, Wenhao Bu, and Bo Yan, Phys. Rev. A 94, 063415 (2016)

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Talk from Dr. Zhensheng Tao:

Time: 3:00 pm,  Jan. 10, 2017, Classroom 423, Building 12, Yuquan campus, Zhejiang University.

Influence of the Material Band Structure on Attosecond Electron Dynamics in Transition Metals

Abstract: Attosecond (10^-18 s) science (attoscience) is a new frontier of science that allows us to investigate the fastest dynamics happening in atoms, molecules and materials. In this talk, I will give a general introduction about what we can learn from attoscience studies and how the dynamics on the attosecond timescales can be measured in experiments. High-order harmonic generation (HHG) so far have served as one of the most powerful tools for such studies. As an example of attoscience study, I will present our recent efforts in JILA to measure attosecond electron dynamics in transition metals by combining HHG light source with angle-resolved photoelectron spectroscopy (ARPES). In this work, we for the first time revealed the strong influence of material band structure on the attosecond electron dynamics in materials, enabled by good energy resolution and polarization, angle-dependent measurements. At the same time, we investigated the electron-electron interactions (screening and scattering) on this shortest timescale ever accessible in a material. 

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Our new photo!

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Talk from Dr. Erhai Zhao:

Time: 10:30 am,  Nov. 8, 2016, Classroom 423, Building 12, Yuquan campus, Zhejiang University.

Competing orders in dipolar Fermi gas

Abstract: Experiments on quantum degenerate Fermi gases of magnetic atoms and dipolar molecules begin to probe their broken symmetry phases dominated by the long-range, anisotropic dipole-dipole interaction. Several candidate phases including the p-wave superfluid, the stripe density wave, and a supersolid have been proposed theoretically for two-dimensional spinless dipolar Fermi gases. Yet the phase boundaries predicted by different approximations vary greatly, and a definitive phase diagram is still lacking. In this talk I will introduce a theory that treats all competing many-body instabilities in the particle-particle and particle-hole channel on equal footing. Then I will present the low temperature phase diagram obtained from numerical solution of the functional renormalization-group flow equations. In particular we find a nontrivial density wave phase at small dipolar tilting angles and strong interactions, but no evidence of the supersolid phase. The critical temperatures of the ordered phases are also estimated.

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Talk from Professor Kaden Hazzard, Rice University.

Time: 10:00 am Oct. 17,  Classroom 423, Building 12,  Yuquan campus, Zhejiang University

Ultracold nonreactive molecules in an optical lattice

ABSTRACT:

Experiments with ultracold molecules in optical lattices have ignited enormous scientific interest due in part to their strong, long-ranged interactions. Previously, it has been presumed that in the absence of chemical reactions a Hubbard model describes the system, as it does for atoms, but with a dipolar interaction added between sites. In contrast to this conventional wisdom, I will describe our finding that the on-site interaction between molecules is modified dramatically from this picture. This is a manifestation of the molecules' chaotic scattering, in contrast to the simple scattering of atoms. One consequence of this new type of interaction is to alter the phase diagram of bosonic molecules. We find that not only is the shape of the phase diagram modified, but that the superfluid displays unique properties that are associated with proximity to exotic phases analogous to spin liquids.

Speaker: Professor Kaden Hazzard:

I grew up in Ohio and attended the Ohio State University for my bachelor's degree. I received my PhD from Cornell University, working with Erich Mueller in 2010. I spent 2010-14 as a postdoc at JILA working with Ana Maria Rey and collaborating with lots of other JILAns. In July 2014, I joined Rice University as an Assistant Professor in the department of physics.

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Welcome the new students:  

Guitao Lv (吕圭桃), Dongyue Wang （王东月）。

And  Pengfei Xu (徐鹏飞）。

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Welcome our new posdoc, Dr. Tao Chen join our group!

2016-8-1

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The molecule review paper published!

http://dx.doi.org/10.1088/0953-4075/49/15/152002

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Vistor: Steven Moses.  From JILA.

2016/5/14 from 9:00-10:00  （浙江大学西溪校区西六116）

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Talk from Dr. Chen Tao, SIOM(上海光机所)

2016/3/31, Thursday, 2:00pm

时间：3月31日星期四下午2：00，地点：小教七会议室。

Title: Anisotropy induced Feshbach resonance: scattering properties of metastable alkaline-earth-like atoms

Abstract: Considering the collisions between ground state Li atom and metastable 171Yb in 3P2 state, unlike the role of the electronic spin degree of freedom in collisions of two alkali-metal atoms, the orbital degrees of freedom from the p electron of Yb atom, which induce not only mixings between different partial waves but also couplings between channels in different fine-structure manifolds, introduce the anisotropic interactions for producing broad-enough Feshbach resonances. The closed-coupling calculation shows that this mechanism is similar to that in highly magnetic atoms, but the resonances also suffer from a large inelastic loss rate to lower-lying fine-structure states or Zeeman sublevels, which will be an obstacle for associating ultraclod polar molecules. However, such a rich mixture of inelastic processes, and the experimental advantage of immunity from intraspecies inelastic collisions for metastable fermions, allow for precise investigations on the interspecies scattering properties.

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小组报告会。

张梦娇博士报告。

题目是： 171Yb原子光晶格钟的研制。张梦娇今年武汉物理数学研究所毕业。主要从事冷原子（研究对象：镱原子）相关物理研究，主要负责镱原子光晶格钟的研制,以及镱原子第二候选钟跃迁激光的产生，参与镱原子Bose-Einstein凝聚体的相关研究。她将主要介绍她在物数所研究Yb原子光晶格钟的工作。

时间：3月14日星期一上午10：00，地点：小教七会议室。

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Group photo:

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Talk from Dr. Zhang Hao, posdoc from MIT.

Nov. 10, 2015, 3:00pm, 教12-201.

Title：Entangled states of 3000 atoms with negative Wigner function

Abstract：
Entangled states of many particles are of interest in quantum information, quantum simulation and precision measurements. We generate an entangled state of 3,000 atoms via interaction with a cavity optical field, and heralded by the detection of a single photon. We measure the spin distributions of this many-atom spin system, and demonstrate a negative Wigner quasi-probability function. This technique can be extended to produce more complicated entangled states, and to realize atomic interferometers that surpass the standard quantum limit.

Update: 2015/11/6


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The lab is ready to go.

From old to new in two month.

The air conditioning works.

update: 2015-10-16

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"Creation of a low-entropy quantum gas of polar molecules in an optical lattice"  now was accepted by Science!

Congradulations, Steven!

http://arxiv.org/abs/1507.02377

update:2015-10-1

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Welcome, Yanhong Zhang, our new assistant secretary, join Yan group!!!

update:2015-9-23

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Welcome, Yan-group members!

About us

Laser cooling of atoms have made an revolution of modern atomic physics. Precise measurements, quantum optics, condensate matter all have benefitted a lot from such technology. Our group is particular interested in

--- developing new techniques and applicaitions of cold atoms,

--- extending laser cooling to polar molecules, 

--- studying many body physics of strongly correlately cold atom system.