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Anderson impurity model

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1164: 1616: 330: 793: 57: 1291: 1159:{\displaystyle H=\sum _{k,\sigma }\epsilon _{k}c_{k\sigma }^{\dagger }c_{k\sigma }+\sum _{j,\sigma }\epsilon _{f}f_{j\sigma }^{\dagger }f_{j\sigma }+U\sum _{j}f_{j\uparrow }^{\dagger }f_{j\uparrow }f_{j\downarrow }^{\dagger }f_{j\downarrow }+\sum _{j,k,\sigma }V_{jk}(e^{ikx_{j}}f_{j\sigma }^{\dagger }c_{k\sigma }+e^{-ikx_{j}}c_{k\sigma }^{\dagger }f_{j\sigma })} 51:. In its simplest form, the model contains a term describing the kinetic energy of the conduction electrons, a two-level term with an on-site Coulomb repulsion that models the impurity energy levels, and a hybridization term that couples conduction and impurity orbitals. For a single impurity, the Hamiltonian takes the form 325:{\displaystyle H=\sum _{k,\sigma }\epsilon _{k}c_{k\sigma }^{\dagger }c_{k\sigma }+\sum _{\sigma }\epsilon _{\sigma }d_{\sigma }^{\dagger }d_{\sigma }+Ud_{\uparrow }^{\dagger }d_{\uparrow }d_{\downarrow }^{\dagger }d_{\downarrow }+\sum _{k,\sigma }V_{k}(d_{\sigma }^{\dagger }c_{k\sigma }+c_{k\sigma }^{\dagger }d_{\sigma })} 1611:{\displaystyle H=\sum _{k,\sigma }\epsilon _{k}c_{k\sigma }^{\dagger }c_{k\sigma }+\sum _{i,\sigma }\epsilon _{d}d_{i\sigma }^{\dagger }d_{i\sigma }+\sum _{i,\sigma ,i'\sigma '}{\frac {U}{2}}n_{i\sigma }n_{i'\sigma '}+\sum _{i,k,\sigma }V_{k}(d_{i\sigma }^{\dagger }c_{k\sigma }+c_{k\sigma }^{\dagger }d_{i\sigma })} 769: 701: 653: 604: 556: 506: 1666: 422: 1195: 1688: 1640: 1255: 1235: 1215: 466: 446: 398: 378: 354: 1281:
Anderson model, which is used to describe impurities which have an orbital, as well as a spin, degree of freedom. This is relevant in
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In the local moment regime, the magnetic moment is present at the impurity site. However, for low enough temperature, the moment is
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For heavy-fermion systems, a lattice of impurities is described by the periodic Anderson model. The one-dimensional model is
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electrons in heavy fermion systems to interact, although they are separated by a distance greater than the
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Schrieffer, J.R.; Wolff, P.A. (September 1966). "Relation between the Anderson and Kondo Hamiltonians".
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The model yields several regimes that depend on the relationship of the impurity energy levels to the
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label the orbital degree of freedom (which can take one of two values), and
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by convention for heavy-fermion systems). The hybridization term allows
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There are other variants of the Anderson model, such as the
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screened to give non-magnetic many-body singlet state.
1676: 1649: 1628: 1294: 1243: 1223: 1203: 1176: 796: 716: 661: 619: 564: 522: 485: 454: 434: 410: 386: 366: 342: 60: 1237:is the impurity creation operator (used instead of 1778: 1776: 1682: 1660: 1634: 1610: 1249: 1229: 1209: 1189: 1158: 763: 696:{\displaystyle \epsilon _{d}+U\approx E_{\rm {F}}} 695: 647: 598: 550: 500: 460: 440: 416: 392: 372: 348: 324: 1285:systems. The SU(4) Anderson model Hamiltonian is 771:, which yields a magnetic moment at the impurity. 1844: 648:{\displaystyle \epsilon _{d}\approx E_{\rm {F}}} 1773: 1745:(1961). "Localized Magnetic States in Metals". 380:is the annihilation operator for the impurity, 1737: 1735: 599:{\displaystyle \epsilon _{d}+U\gg E_{\rm {F}}} 39:. It is often applied to the description of 1826: 1824: 1822: 551:{\displaystyle \epsilon _{d}\gg E_{\rm {F}}} 1732: 1819: 1741: 782: 1835:. New York: Cambridge University Press. 1845: 1830: 1833:The Kondo Problem to Heavy Fermions 428:. The onโ€“site Coulomb repulsion is 16:Hamiltonian used in quantum physics 13: 736: 687: 639: 590: 542: 492: 14: 1869: 1272: 1197:is the position of impurity site 1605: 1537: 1153: 1036: 993: 975: 962: 944: 360:of a conduction electron, and 319: 257: 223: 208: 198: 183: 1: 1725: 606:, which has no local moment. 7: 1698: 1283:carbon nanotube quantum dot 501:{\displaystyle E_{\rm {F}}} 400:is the conduction electron 10: 1874: 471: 468:gives the hybridization. 31:that is used to describe 1858:Condensed matter physics 43:-type problems, such as 1805:10.1103/PhysRev.149.491 417:{\displaystyle \sigma } 21:Anderson impurity model 1853:Quantum lattice models 1831:Hewson, A. C. (1993). 1767:10.1103/PhysRev.124.41 1684: 1662: 1636: 1612: 1251: 1231: 1211: 1191: 1160: 765: 697: 649: 600: 552: 502: 462: 442: 418: 394: 374: 350: 326: 25:Philip Warren Anderson 1720:Anderson localization 1685: 1663: 1637: 1613: 1252: 1232: 1212: 1192: 1190:{\displaystyle x_{j}} 1161: 783:Heavy-fermion systems 766: 698: 650: 601: 553: 503: 463: 443: 419: 395: 375: 358:annihilation operator 351: 327: 1674: 1647: 1626: 1292: 1241: 1221: 1201: 1174: 794: 714: 659: 617: 562: 520: 483: 452: 432: 408: 384: 364: 340: 58: 1797:1966PhRv..149..491S 1759:1961PhRv..124...41A 1591: 1557: 1404: 1344: 1139: 1079: 984: 953: 906: 846: 308: 274: 217: 192: 161: 110: 33:magnetic impurities 1695:for the impurity. 1680: 1661:{\displaystyle i'} 1658: 1632: 1608: 1574: 1540: 1526: 1455: 1387: 1376: 1327: 1316: 1247: 1227: 1207: 1187: 1156: 1122: 1062: 1022: 967: 936: 935: 889: 878: 829: 818: 761: 693: 645: 596: 548: 498: 458: 438: 414: 390: 370: 346: 322: 291: 260: 246: 203: 178: 147: 136: 93: 82: 1683:{\displaystyle n} 1635:{\displaystyle i} 1505: 1464: 1421: 1361: 1301: 1250:{\displaystyle d} 1230:{\displaystyle f} 1210:{\displaystyle j} 1001: 926: 863: 803: 461:{\displaystyle V} 441:{\displaystyle U} 393:{\displaystyle k} 373:{\displaystyle d} 349:{\displaystyle c} 231: 127: 67: 1865: 1837: 1836: 1828: 1817: 1816: 1780: 1771: 1770: 1739: 1689: 1687: 1686: 1681: 1667: 1665: 1664: 1659: 1657: 1641: 1639: 1638: 1633: 1617: 1615: 1614: 1609: 1604: 1603: 1590: 1585: 1570: 1569: 1556: 1551: 1536: 1535: 1525: 1501: 1500: 1499: 1491: 1478: 1477: 1465: 1457: 1454: 1453: 1445: 1417: 1416: 1403: 1398: 1386: 1385: 1375: 1357: 1356: 1343: 1338: 1326: 1325: 1315: 1256: 1254: 1253: 1248: 1236: 1234: 1233: 1228: 1216: 1214: 1213: 1208: 1196: 1194: 1193: 1188: 1186: 1185: 1165: 1163: 1162: 1157: 1152: 1151: 1138: 1133: 1121: 1120: 1119: 1118: 1092: 1091: 1078: 1073: 1061: 1060: 1059: 1058: 1035: 1034: 1021: 997: 996: 983: 978: 966: 965: 952: 947: 934: 919: 918: 905: 900: 888: 887: 877: 859: 858: 845: 840: 828: 827: 817: 770: 768: 767: 762: 754: 753: 741: 740: 739: 726: 725: 702: 700: 699: 694: 692: 691: 690: 671: 670: 654: 652: 651: 646: 644: 643: 642: 629: 628: 605: 603: 602: 597: 595: 594: 593: 574: 573: 557: 555: 554: 549: 547: 546: 545: 532: 531: 507: 505: 504: 499: 497: 496: 495: 467: 465: 464: 459: 447: 445: 444: 439: 423: 421: 420: 415: 399: 397: 396: 391: 379: 377: 376: 371: 356:operator is the 355: 353: 352: 347: 331: 329: 328: 323: 318: 317: 307: 302: 287: 286: 273: 268: 256: 255: 245: 227: 226: 216: 211: 202: 201: 191: 186: 171: 170: 160: 155: 146: 145: 135: 123: 122: 109: 104: 92: 91: 81: 49:Kondo insulators 1873: 1872: 1868: 1867: 1866: 1864: 1863: 1862: 1843: 1842: 1841: 1840: 1829: 1820: 1785:Physical Review 1781: 1774: 1743:Anderson, P. W. 1740: 1733: 1728: 1701: 1693:number operator 1691:represents the 1675: 1672: 1671: 1650: 1648: 1645: 1644: 1627: 1624: 1623: 1596: 1592: 1586: 1578: 1562: 1558: 1552: 1544: 1531: 1527: 1509: 1492: 1484: 1483: 1479: 1470: 1466: 1456: 1446: 1438: 1425: 1409: 1405: 1399: 1391: 1381: 1377: 1365: 1349: 1345: 1339: 1331: 1321: 1317: 1305: 1293: 1290: 1289: 1275: 1242: 1239: 1238: 1222: 1219: 1218: 1202: 1199: 1198: 1181: 1177: 1175: 1172: 1171: 1144: 1140: 1134: 1126: 1114: 1110: 1100: 1096: 1084: 1080: 1074: 1066: 1054: 1050: 1043: 1039: 1027: 1023: 1005: 989: 985: 979: 971: 958: 954: 948: 940: 930: 911: 907: 901: 893: 883: 879: 867: 851: 847: 841: 833: 823: 819: 807: 795: 792: 791: 785: 749: 745: 735: 734: 730: 721: 717: 715: 712: 711: 686: 685: 681: 666: 662: 660: 657: 656: 638: 637: 633: 624: 620: 618: 615: 614: 589: 588: 584: 569: 565: 563: 560: 559: 541: 540: 536: 527: 523: 521: 518: 517: 491: 490: 486: 484: 481: 480: 474: 453: 450: 449: 433: 430: 429: 409: 406: 405: 385: 382: 381: 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1848: 1834: 1827: 1825: 1823: 1814: 1810: 1806: 1802: 1798: 1794: 1790: 1786: 1779: 1777: 1768: 1764: 1760: 1756: 1752: 1748: 1744: 1738: 1736: 1731: 1721: 1718: 1716: 1713: 1711: 1708: 1706: 1705:Hubbard model 1703: 1702: 1696: 1694: 1690: 1677: 1668: 1654: 1651: 1629: 1600: 1597: 1593: 1587: 1582: 1579: 1575: 1571: 1566: 1563: 1559: 1553: 1548: 1545: 1541: 1532: 1528: 1522: 1519: 1516: 1513: 1510: 1506: 1502: 1496: 1493: 1488: 1485: 1480: 1474: 1471: 1467: 1461: 1458: 1450: 1447: 1442: 1439: 1435: 1432: 1429: 1426: 1422: 1418: 1413: 1410: 1406: 1400: 1395: 1392: 1388: 1382: 1378: 1372: 1369: 1366: 1362: 1358: 1353: 1350: 1346: 1340: 1335: 1332: 1328: 1322: 1318: 1312: 1309: 1306: 1302: 1298: 1295: 1288: 1287: 1286: 1284: 1280: 1270: 1268: 1264: 1260: 1244: 1224: 1204: 1182: 1178: 1148: 1145: 1141: 1135: 1130: 1127: 1123: 1115: 1111: 1107: 1104: 1101: 1097: 1093: 1088: 1085: 1081: 1075: 1070: 1067: 1063: 1055: 1051: 1047: 1044: 1040: 1031: 1028: 1024: 1018: 1015: 1012: 1009: 1006: 1002: 998: 990: 986: 980: 972: 968: 959: 955: 949: 941: 937: 931: 927: 923: 920: 915: 912: 908: 902: 897: 894: 890: 884: 880: 874: 871: 868: 864: 860: 855: 852: 848: 842: 837: 834: 830: 824: 820: 814: 811: 808: 804: 800: 797: 790: 789: 788: 780: 778: 758: 755: 750: 746: 742: 731: 727: 722: 718: 709: 705: 682: 678: 675: 672: 667: 663: 634: 630: 625: 621: 612: 608: 585: 581: 578: 575: 570: 566: 537: 533: 528: 524: 515: 514:empty orbital 511: 510: 509: 487: 479: 469: 455: 435: 427: 411: 403: 387: 367: 359: 343: 314: 310: 304: 299: 296: 292: 288: 283: 280: 276: 270: 265: 261: 252: 248: 242: 239: 236: 232: 228: 219: 213: 204: 194: 188: 179: 175: 172: 167: 163: 157: 152: 148: 142: 138: 132: 128: 124: 119: 116: 112: 106: 101: 98: 94: 88: 84: 78: 75: 72: 68: 64: 61: 54: 53: 52: 50: 46: 45:heavy fermion 42: 38: 34: 30: 26: 22: 1832: 1788: 1784: 1753:(1): 41โ€“53. 1750: 1746: 1710:Kondo effect 1670: 1643: 1621: 1276: 1258: 1169: 786: 774: 708:local moment 707: 611:intermediate 610: 513: 475: 335: 47:systems and 41:Kondo effect 35:embedded in 20: 18: 1715:Kondo model 710:regime for 613:regime for 516:regime for 478:Fermi level 424:labels the 29:Hamiltonian 1847:Categories 1726:References 1267:Hill limit 402:wavevector 336:where the 1747:Phys. Rev 1601:σ 1588:† 1583:σ 1567:σ 1554:† 1549:σ 1523:σ 1507:∑ 1494:σ 1475:σ 1448:σ 1433:σ 1423:∑ 1414:σ 1401:† 1396:σ 1379:ϵ 1373:σ 1363:∑ 1354:σ 1341:† 1336:σ 1319:ϵ 1313:σ 1303:∑ 1149:σ 1136:† 1131:σ 1102:− 1089:σ 1076:† 1071:σ 1019:σ 1003:∑ 994:↓ 981:† 976:↓ 963:↑ 950:† 945:↑ 928:∑ 916:σ 903:† 898:σ 881:ϵ 875:σ 865:∑ 856:σ 843:† 838:σ 821:ϵ 815:σ 805:∑ 747:ϵ 743:≪ 728:≪ 719:ϵ 679:≈ 664:ϵ 631:≈ 622:ϵ 582:≫ 567:ϵ 534:≫ 525:ϵ 412:σ 315:σ 305:† 300:σ 284:σ 271:† 266:σ 243:σ 233:∑ 224:↓ 214:† 209:↓ 199:↑ 189:† 184:↑ 168:σ 158:† 153:σ 143:σ 139:ϵ 133:σ 129:∑ 120:σ 107:† 102:σ 85:ϵ 79:σ 69:∑ 1813:55838235 1699:See also 1655:′ 1497:′ 1489:′ 1451:′ 1443:′ 1793:Bibcode 1755:Bibcode 1263:orbital 472:Regimes 27:, is a 1811:  1622:where 1217:, and 1170:where 448:, and 404:, and 37:metals 1809:S2CID 1279:SU(4) 777:Kondo 1642:and 706:The 609:The 512:The 426:spin 19:The 1801:doi 1789:149 1763:doi 1751:124 655:or 558:or 1849:: 1821:^ 1807:. 1799:. 1787:. 1775:^ 1761:. 1749:. 1734:^ 1269:. 508:: 1815:. 1803:: 1795:: 1769:. 1765:: 1757:: 1678:n 1652:i 1630:i 1618:, 1606:) 1598:i 1594:d 1580:k 1576:c 1572:+ 1564:k 1560:c 1546:i 1542:d 1538:( 1533:k 1529:V 1520:, 1517:k 1514:, 1511:i 1503:+ 1486:i 1481:n 1472:i 1468:n 1462:2 1459:U 1440:i 1436:, 1430:, 1427:i 1419:+ 1411:i 1407:d 1393:i 1389:d 1383:d 1370:, 1367:i 1359:+ 1351:k 1347:c 1333:k 1329:c 1323:k 1310:, 1307:k 1299:= 1296:H 1261:- 1259:f 1245:d 1225:f 1205:j 1183:j 1179:x 1166:, 1154:) 1146:j 1142:f 1128:k 1124:c 1116:j 1112:x 1108:k 1105:i 1098:e 1094:+ 1086:k 1082:c 1068:j 1064:f 1056:j 1052:x 1048:k 1045:i 1041:e 1037:( 1032:k 1029:j 1025:V 1016:, 1013:k 1010:, 1007:j 999:+ 991:j 987:f 973:j 969:f 960:j 956:f 942:j 938:f 932:j 924:U 921:+ 913:j 909:f 895:j 891:f 885:f 872:, 869:j 861:+ 853:k 849:c 835:k 831:c 825:k 812:, 809:k 801:= 798:H 759:U 756:+ 751:d 737:F 732:E 723:d 703:. 688:F 683:E 676:U 673:+ 668:d 640:F 635:E 626:d 591:F 586:E 579:U 576:+ 571:d 543:F 538:E 529:d 493:F 488:E 456:V 436:U 388:k 368:d 344:c 332:, 320:) 311:d 297:k 293:c 289:+ 281:k 277:c 262:d 258:( 253:k 249:V 240:, 237:k 229:+ 220:d 205:d 195:d 180:d 176:U 173:+ 164:d 149:d 125:+ 117:k 113:c 99:k 95:c 89:k 76:, 73:k 65:= 62:H

Index

Philip Warren Anderson
Hamiltonian
magnetic impurities
metals
Kondo effect
heavy fermion
Kondo insulators
annihilation operator
wavevector
spin
Fermi level
Kondo
orbital
Hill limit
SU(4)
carbon nanotube quantum dot
number operator
Hubbard model
Kondo effect
Kondo model
Anderson localization


Anderson, P. W.
Bibcode
1961PhRv..124...41A
doi
10.1103/PhysRev.124.41

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