Pub Date : 2023-08-28DOI: 10.1103/physreva.108.022815
R. Brienza, Y. Lu, C. Wang, S. Kanungo, T. Killian, F. Dunning, J. Burgdörfer, S. Yoshida
{"title":"Microwave spectroscopy of low-l singlet strontium Rydberg states at intermediate n, 50","authors":"R. Brienza, Y. Lu, C. Wang, S. Kanungo, T. Killian, F. Dunning, J. Burgdörfer, S. Yoshida","doi":"10.1103/physreva.108.022815","DOIUrl":"https://doi.org/10.1103/physreva.108.022815","url":null,"abstract":"","PeriodicalId":48702,"journal":{"name":"Physical Review a","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48480175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-28DOI: 10.1103/PhysRevA.108.022427
Lifeng Zhang, Zhihua Chen, S. Fei
Quantum entanglement lies at the heart in quantum information processing tasks. Although many criteria have been proposed, efficient and scalable methods to detect the entanglement of generally given quantum states are still not available yet, particularly for high-dimensional and multipartite quantum systems. Based on FixMatch and Pseudo-Label method, we propose a deep semi-supervised learning model with a small portion of labeled data and a large portion of unlabeled data. The data augmentation strategies are applied in this model by using the convexity of separable states and performing local unitary operations on the training data. We verify that our model has good generalization ability and gives rise to better accuracies compared to traditional supervised learning models by detailed examples.
{"title":"Entanglement verification with deep semisupervised machine learning","authors":"Lifeng Zhang, Zhihua Chen, S. Fei","doi":"10.1103/PhysRevA.108.022427","DOIUrl":"https://doi.org/10.1103/PhysRevA.108.022427","url":null,"abstract":"Quantum entanglement lies at the heart in quantum information processing tasks. Although many criteria have been proposed, efficient and scalable methods to detect the entanglement of generally given quantum states are still not available yet, particularly for high-dimensional and multipartite quantum systems. Based on FixMatch and Pseudo-Label method, we propose a deep semi-supervised learning model with a small portion of labeled data and a large portion of unlabeled data. The data augmentation strategies are applied in this model by using the convexity of separable states and performing local unitary operations on the training data. We verify that our model has good generalization ability and gives rise to better accuracies compared to traditional supervised learning models by detailed examples.","PeriodicalId":48702,"journal":{"name":"Physical Review a","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44075381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-25DOI: 10.1103/physreva.108.022425
Stefano Guerrini, M. Win, A. Conti
This paper introduces photon-varied quantum states (PVQSs), which generalize the nonclassical states obtained via photon addition or subtraction operations. We provide a unified characterization of PVQSs in terms of characteristic function, quasiprobability distribution, Fock representation, and Mandel Q parameter. In the special case of photon-varied Gaussian states (PVGSs), the characteristic functions and the quasiprobability distributions are found to be in a simple canonical product structure. Necessary and sufficient conditions for the negativity of the quasiprobability distributions are also obtained for PVGSs. The unified characterization enables the design and analysis of quantum systems that exploit the non-Gaussian properties of PVQSs.
{"title":"Photon-varied quantum states: Unified characterization","authors":"Stefano Guerrini, M. Win, A. Conti","doi":"10.1103/physreva.108.022425","DOIUrl":"https://doi.org/10.1103/physreva.108.022425","url":null,"abstract":"This paper introduces photon-varied quantum states (PVQSs), which generalize the nonclassical states obtained via photon addition or subtraction operations. We provide a unified characterization of PVQSs in terms of characteristic function, quasiprobability distribution, Fock representation, and Mandel Q parameter. In the special case of photon-varied Gaussian states (PVGSs), the characteristic functions and the quasiprobability distributions are found to be in a simple canonical product structure. Necessary and sufficient conditions for the negativity of the quasiprobability distributions are also obtained for PVGSs. The unified characterization enables the design and analysis of quantum systems that exploit the non-Gaussian properties of PVQSs.","PeriodicalId":48702,"journal":{"name":"Physical Review a","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43201682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-25DOI: 10.1103/physreva.108.023522
P. Brandão
{"title":"Ability of loss to increase the spatial coherence of guided waves","authors":"P. Brandão","doi":"10.1103/physreva.108.023522","DOIUrl":"https://doi.org/10.1103/physreva.108.023522","url":null,"abstract":"","PeriodicalId":48702,"journal":{"name":"Physical Review a","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48707020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-24DOI: 10.1103/PhysRevA.108.L021502
Haowei Xu, Hao Tang, Guoqing Wang, Changhao Li, Boning Li, P. Cappellaro, Ju Li
The radiative excitation of the 8.3 eV isomeric state of thorium-229 is an outstanding challenge due to the lack of tunable far-ultraviolet (F-UV) sources. In this work, we propose an efficient two-photon pumping scheme for thorium-229 using the optonuclear quadrupolar effect, which only requires a 300 nm UV-B pumping laser. We further demonstrate that population inversion between the nuclear isomeric and ground states can be achieved at room temperature using a two-step pumping process. The nuclear laser, which has been pursued for decades, may be realized using a Watt-level UV-B pumping laser and ultrawide bandgap thorium compounds (e.g., $rm ThF_4$, $rm Na_2ThF_6$, or $rm K_2ThF_6$) as the gain medium.
{"title":"Solid-state Th229 nuclear laser with two-photon pumping","authors":"Haowei Xu, Hao Tang, Guoqing Wang, Changhao Li, Boning Li, P. Cappellaro, Ju Li","doi":"10.1103/PhysRevA.108.L021502","DOIUrl":"https://doi.org/10.1103/PhysRevA.108.L021502","url":null,"abstract":"The radiative excitation of the 8.3 eV isomeric state of thorium-229 is an outstanding challenge due to the lack of tunable far-ultraviolet (F-UV) sources. In this work, we propose an efficient two-photon pumping scheme for thorium-229 using the optonuclear quadrupolar effect, which only requires a 300 nm UV-B pumping laser. We further demonstrate that population inversion between the nuclear isomeric and ground states can be achieved at room temperature using a two-step pumping process. The nuclear laser, which has been pursued for decades, may be realized using a Watt-level UV-B pumping laser and ultrawide bandgap thorium compounds (e.g., $rm ThF_4$, $rm Na_2ThF_6$, or $rm K_2ThF_6$) as the gain medium.","PeriodicalId":48702,"journal":{"name":"Physical Review a","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44101848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-24DOI: 10.1103/physreva.108.022813
M. Jiang, R. Grobe, Q. Su
{"title":"Impact of spatially periodic inhomogeneities on the photon-induced pair creation","authors":"M. Jiang, R. Grobe, Q. Su","doi":"10.1103/physreva.108.022813","DOIUrl":"https://doi.org/10.1103/physreva.108.022813","url":null,"abstract":"","PeriodicalId":48702,"journal":{"name":"Physical Review a","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42954171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}