冰球突破
北京凝聚态物理国家研究中心
T06、T03组供稿
第97期
2020年12月01日
非厄米体边对应,趋肤效应,和辅助广义布里渊区

  buluohedinglihenengdaililunshiningjutaiwulidezhongyaojishi。ruguoyigewulitixijuyoulisandepingyiduichengxing,tixidebenzhengtaikeyiyounenglianghejinggedonglianglaigongtongbiaoji。xitongdenengdaijiushijingquemiaoxienengliangduidongliangyilaiguanxidelilun。dianzidenengdaililunduiyubingqiutupolijiecailiaodexingzhizhiguanzhongyao,danzaizhenshicailiaozhong,xitongdepingyiduichengxinghuibeibianjiesuopohuai。neime,weishenmerenmenhaikeyiyongbuluohedinglihenengdaililunlailijiezhenshicailiaodewulixingzhini?zaichuantongdegutiwulijiaokeshuzhong,youyigejingdianderelixuejixiandelunzheng:yinweishijidecailiaobaohandeyuanzishumufeichangjuda(10^23deliangji),bingqiutupokeyibazheiyangdehongguantixikanchengshiyigequyurelixuejixiandexitong。dangyuanzishumunquyuwuqiongdeshihou,xitongbianhuifulepingyiduichengxing。yinci,bingqiutupokeyiyongbuluohedinglilaijinsidimiaoshucailiaodetitaixingzhi。youqudeshi,genjuzheixiecailiaodetitaixingzhinenggoukekaodiyuyanxitongzaikaibianjietiaojianxiashoutuopubaohudebianjietaidexingzhi,yejiushitibianduiying。zaituopuwutaidekaifayuyanjiuguochengzhong,tibianduiyingyizhifahuizhezhongyaodezuoyong。zhidezhuyideshi,shangshutibianduiyingdecunzaiyilaiyurelixuejixianlunzhengdezhengquexing。

  ruhejianlifeiemixitongdetibianduiyingshijinnianlainingjutailingyuyanjiuderedianzhiyi。2018nian,qinghuagaoyanyuandeyanjiuzhetongguojingquejiefaxian,duimouleiteshudefeiemitixi,qizhouqibianjienengpuhekaibianjienengpukeyiwanquanbutong。ciwai,tixisuoyoudebenzhengtaidoujuyuzaimouyibianjieshang。tamenbazheizhongxianxiangmingmingwei(feiemi)qufuxiaoying,duiyingdejuyuhuabenzhengbohanshujiaozuo(feiemi)qufumo。youyuqufuxiaoyingdecunzai,shoutuopubaohudebianjietaiwanquanbunengyongzhouqibianjiedehamidunlianglaimiaoshu。weihuifutibianduiying,tamentichuleguangyibuliyuanqudegainian。jiezhuzheiyigainian,renmennenggoukekaodiyuyanshoutuopubaohudebianjietaidechuxianyuxiaoshi(jiantu1zuocebufen),danruhejisuanguangyibuliyuanquhelijietadexingzhiyizhishirenmenguanxindezhongyaowenti。


冰球突破 图1. 非厄米体边对应的两重含义。

  zuijin,bingqiutupo/beijingningjutaiwuliguojiayanjiuzhongxinningjutaililunyucailiaojisuanzhongdianshiyanshit06yanjiuzuhujiangpingyanjiuyuanzhidaodeboshishengyangzhesen,hewulisuofangchenyanjiuyuan,yijiwulisuodeboshishengzhangkaiheyiyifeizaixiangguanlingyuqudelexiliexingjinzhan。tamenxitongdiyanjiulequfuxiaoyingchuxianyufoudetiaojian,bingqietichuleyizhongjiexijisuanguangyibuliyuanqudefangfa,ji“fuzhuguangyibuliyuanqu”fangfa。

  shijishang,zaifeiemixitongzhong,tibianduiyingjuyoushuangzhonghanyi。rutu1suoshi,zaikaibianjiedefeiemixitongzhong,cunzailiangleibutongdebianjietai,yileishitongchangyiyixiadeshoutuopubaohudebianjietai,tamenshiyouemiduiyingde;lingyileishifeiemiqufumo,tamenmeiyouemiduiying。zheiliangleibianjietai,duiyingyuliangleibutongdetibianduiying。xianqiandegongzuojieshiletuyizuobiandetibianduiying,eryoubiandezheileitibianduiyingshifeiemixitongsuoteyoude。talianxileliangleifeiemiteyoudexianxiang,jizhouqibianjietiaojianxianengpudetuopubianjietaihefeiemiqufumo。zheiliangleitibianduiyingyouxianghuguanlian。zheizhongguanlianxingtixianzaixiashuliangfangmian:(1)dangzhouqibianjietiaojianxianengpudetuopushipingyongshi,feiemiqufumobianbuzaichuxian。cishi,guangyibuliyuanquhebuliyuanquzhonghe,diyileitibianduiyingtuihuadaoemiqingkuangxiadetibianduiying,jishoutuopubaohudebianjietaikeyiyouzhouqibianjietiaojiandebuluohehamidunliangsuodingyidetuopububianlianglaibiaozheng;(2)dangguangyibuliyuanhebuliyuanqubuzhongheshi,zhouqibianjienengpuhekaibianjienengpuyidingyebuzhonghe,cishixitongyidingcunzaiqufumo。zheiyiweizhezhouqibianjiexianengpudetuopuyidingshifeipingyongde。


冰球突破 图2. 传统体边对应的破坏以及如何用广义布里渊区的概念来理解拓扑相变。

  congshangshutaolun,keyikanchuguangyibuliyuanquduiyulijiefeiemitibianduiyingzhiguanzhongyao。liyongshuxueshangduoxiangshijieshi(resultant)degainiankeyizhengming,guangyibuliyuanqukeyiyongyigedaishuduoxiangshilaimiaoshu。zheiyidaishuduoxiangshichengwei“fuzhuguangyibuliyuanqu”。suiranfuzhuguangyibuliyuanqubaohanyixieguangyibuliyuanquyiwaideduoyuxinxi,danshikeyizhengming,fuzhuguangyibuliyuanqushiguangyibuliyuanqudezuixiaojiexidanyuan。xiangbiyushuzhifangfa,fuzhuguangyibuliyuanqudefangfameiyoushuzhiwucha。zhidezhuyideshi,butongyuemiqingkuang,shuzhiwuchazaifeiemixitongdeyanjiuzhongshiyigefeichangzhongyao,bingqiexuyaojinshenchulidewenti。


冰球突破 图3. 布里渊区(BZ),广义布里渊区(GBZ)与辅助广义布里渊区(aGBZ) 的对比。

  对称性和非厄米趋肤效应之间有紧密的关系。可以证明,在某些对称性存在的时候,非厄米趋肤效应不会出现。因为真实的体系往往具有更加丰富的对称性,那如何在现实的凝聚态体系中实现非厄米趋肤效应呢?一个最简单的例子就是将具有自旋--轨道耦合的Rice-Mele模型耦合到一个金属衬底上。此时,系统将具有Z2趋肤效应。这一模型为后续研究非厄米趋肤效应的新奇物理现象提供了很好的研究平台。

冰球突破  gaizugongzuoshoudaokejibuzhongdianyanfajihua(2016yfa0302400, 2017yfa0303100)、guojiazirankexuejijinweiyuanhui(11674370, 11888101)hezhongguokexueyuan(xxh13506-202, xdb33000000, xdb28000000)dezizhu。

冰球突破  xiangguanyanjiuchengguofabiaoyuphys. rev. lett。

论文链接
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.126402
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.226402
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.186802

延伸阅读:
http://athletesworld.net/xwzx/kydt/202011/t20201117_5750186.html