I review theoretical ideas and implications of experiments for the gap structure and symmetry of the Fe-based superconductors. Unlike any other class of unconventional superconductors, one has in these systems the possibility to tune the interactions by small changes in pressure, doping or disorder. Thus, measurements of order parameter evolution with these parameters should enable a deeper understanding of the underlying interactions. I briefly review the “standard paradigm” for s-wave pairing in these systems, and then focus on developments in the past several years which have challenged this picture. I further discuss the reasons for the apparent close competition between pairing in s- and d-wave channels, particularly in those systems where one type of Fermi surface pocket – hole or electron – is missing. Observation of a transition between s- and d-wave symmetry, possibly via a time reversal symmetry breaking “s + id” state, would provide an important confirmation of these ideas. Several proposals for detecting these novel phases are discussed, including the appearance of order parameter collective modes in Raman and optical conductivities. Transitions between two different types of s-wave states, involving various combinations of signs on Fermi surface pockets, can also proceed through a -breaking “s + is” state. I discuss recent work that suggests pairing may take place away from the Fermi level over a surprisingly large energy range, as well as the effect of glide plane symmetry of the Fe-based systems on the superconductivity, including various exotic, time and translational invariance breaking pair states that have been proposed. Finally, I address disorder issues, and the various ways systematic introduction of disorder can (and cannot) be used to extract information on gap symmetry and structure.
Je passe en revue les idées théoriques et les implications des expériences sur la structure et la symétrie du gap dans les supraconducteurs à base de fer. Contrairement à la majorité des autres classes de supraconducteurs non conventionnels, il est ici possible de modifier les interactions par de faibles changements de pression, par dopage ou par l'introduction de désordre. Aussi, des mesures de l'évolution du paramètre d'ordre en fonction de ces paramètres de contrôle devraient permettre une compréhension fine des interactions sous-jacentes responsables de l'appariement des électrons. Je rappelle brièvement le « paradigme standard » de la supraconductivité de type s dans ces composés, et discute plus finement les développements effectués ces dernières années qui mettent en cause ce modèle. Je discute les raisons qui semblent conforter une compétition entre des appariements de type s et d, particulièrement dans les systèmes pour lesquels une des poches de la surface de Fermi – électrons ou trous – est absente. L'observation d'une transition entre symétries s et d, éventuellement associée à un état « s + id » brisant la symétrie par renversement du temps, serait une importante confirmation de ces idées. Plusieurs propositions permettant d'observer ces transitions sont discutées, incluant l'apparition de modes collectifs du paramètre d'ordre dans les expériences d'effet Raman ou de conductivité optique. Des transitions entre différents types d'états de type s impliquant diverses combinaisons de signes sur les poches de la surface de Fermi peuvent aussi se produire à travers un état « s + is » brisant . Je discute des travaux récents qui suggèrent que l'appariement peut, de façon surprenante, s'effectuer sur une grande gamme d'énergies autour de l'énergie de Fermi, ainsi que de l'effet sur la supraconductivité de la symétrie de plan de glissement miroir des composés au fer et des divers états de paires exotiques brisant l'invariance par renversement du temps ou par translation qui ont été proposés. Finalement, je considère les problèmes associés au désordre et comment diverses façons d'introduire un désordre contrôlé peuvent (ou non) permettre d'obtenir des informations sur la structure et la symétrie du gap.
Mot clés : Supraconducteurs à base de fer, Supraconductivité non conventionnelle, Brisure de symétrie par inversion du temps, Supraconductivité multibandes, Désordre électronique
Peter J. Hirschfeld 1
@article{CRPHYS_2016__17_1-2_197_0, author = {Peter J. Hirschfeld}, title = {Using gap symmetry and structure to reveal the pairing mechanism in {Fe-based} superconductors}, journal = {Comptes Rendus. Physique}, pages = {197--231}, publisher = {Elsevier}, volume = {17}, number = {1-2}, year = {2016}, doi = {10.1016/j.crhy.2015.10.002}, language = {en}, }
Peter J. Hirschfeld. Using gap symmetry and structure to reveal the pairing mechanism in Fe-based superconductors. Comptes Rendus. Physique, Volume 17 (2016) no. 1-2, pp. 197-231. doi : 10.1016/j.crhy.2015.10.002. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2015.10.002/
[1] J. Am. Chem. Soc., 130 (2008), p. 3296
[2] arXiv
|[3] Phys. Today, 68 (2015) no. 6, p. 46
[4] Adv. Phys., 62 (2014), p. 453
[5] Rep. Prog. Phys., 74 (2011), p. 124508
[6] Annu. Rev. Condens. Matter Phys., 3 (2012), p. 57
[7] Annu. Rev., 2 (2011), p. 121
[8] Phys. Rep., 250 (1995), p. 329
[9] Rev. Mod. Phys., 72 (2000), p. 969
[10] New J. Phys., 12 (2010)
[11] Phys. Rev. Lett., 101 (2008)
[12] Phys. Rev. Lett., 101 (2008)
[13] New J. Phys., 11 (2009)
[14] Phys. Rev. B, 107 (2011)
[15] Rev. Mod. Phys., 63 (1991), p. 239
[16] New J. Phys., 15 (2013)
[17] Physics, 4 (2011), p. 26
[18] J. Phys. Soc. Jpn., 81 (2012)
[19] Phys. Rev. B, 88 (2013)
[20] J. Phys. Soc. Jpn., 77 (2008), p. 103705
[21] Phys. Rev. Lett., 101 (2008)
[22] Europhys. Lett., 83 (2008), p. 57001
[23] Europhys. Lett., 87 (2009), p. 27012
[24] J. Phys. Soc. Jpn., 78 (2009), p. 103702
[25] Phys. Rev. B, 81 (2010)
[26] J. Phys. Soc. Jpn., 79 (2010)
[27] Phys. Rev. B, 81 (2010)
[28] Eur. Phys. J. B, 85 (2012), p. 159
[29] Phys. Rev. B, 83 (2011)
[30] Nature, 456 (2008), p. 930
[31] Phys. Rev. Lett., 102 (2009)
[32] Nat. Phys., 6 (2010), p. 178
[33] Phys. Rev. Lett., 102 (2009)
[34] Phys. Rev. Lett., 103 (2009)
[35] Phys. Rev. B, 82 (2010)
[36] Phys. Rev. B, 81 (2010)
[37] Phys. Rev. Lett., 103 (2009)
[38] J. Phys. Condens. Matter, 22 (2010), p. 142202
[39] Nat. Phys., 6 (2010), p. 260
[40] Science, 328 (2010), p. 474
[41] Phys. Rev. B, 89 (2014)
[42] Phys. Rev. B, 81 (2010)
[43] Rev. Mod. Phys., 72 (2000), p. 969
[44] Phys. Rev. Lett., 71 (1993), p. 2134
[45] Europhys. Lett., 96 (2011), p. 27014
[46] Phys. Rev. B, 80 (2009)
[47] Phys. Rev. B, 78 (2008)
[48] Phys. Rev. B, 78 (2008)
[49] Phys. Rev. B, 79 (2009)
[50] Phys. Rev. B, 83 (2011)
[51] Rev. Mod. Phys., 87 (2015), p. 855
[52] C. R. Physique, 17 (2016) no. 1–2, pp. 60-89 ( this issue )
[53] C. R. Physique, 17 (2016) no. 1–2, pp. 36-59 ( this issue )
[54] Phys. Rev. B, 81 (2010)
[55] Phys. Rev. Lett., 102 (2009)
[56] Nat. Mater., 12 (2013), p. 392
[57] Rep. Prog. Phys., 74 (2011), p. 124505
[58] Phys. Rev. B, 79 (2009)
[59] Proc. Natl. Acad. Sci. USA, 111 (2014), pp. 16309-16313
[60] Phys. Rev. B, 332 (2011), p. 1410
[61] Phys. Rev. B, 90 (2014)
[62] Phys. Rev. Lett., 115 (2015)
[63] Phys. Rev. B, 81 (2010)
[64] Phys. Rev. B, 84 (2011)
[65] Phys. Rev. B, 84 (2011)
[66] Phys. Rev. B, 82 (2010)
[67] Phys. Rev. B, 82 (2010)
[68] arXiv
|[69] Phys. Rev. Lett., 3 (1959), p. 552
[70] Fiz. Met. Metalloved., 8 (1959), p. 503
[71] Sov. Phys. JETP, 63 (1972), p. 1059
[72] Supercond. Sci. Technol., 28 (2015)
[73]
, Johns Hopkins University, 2010 (Ph.D. thesis)[74] Phys. Rev. B, 75 (2007)
[75] Phys. Rev. B, 78 (2008)
[76] Phys. Rev. B, 78 (2008)
[77] Phys. Rev. B, 77 (2008)
[78] Phys. Rev. B, 78 (2008)
[79] Phys. Rev. Lett., 100 (2008)
[80] J. Phys. Condens. Matter, 20 (2008), p. 425203
[81] Phys. Rev. B, 77 (2008)
[82] Phys. Rev. Lett., 101 (2008)
[83] Europhys. Lett., 82 (2008), p. 37007
[84] Phys. Rev. Lett., 101 (2008)
[85] Phys. Rev. B, 77 (2008)
[86] arXiv
, 2008 |[87] Phys. Rev. B, 78 (2008)
[88] Phys. Rev. B, 81 (2010)
[89] Phys. Rev. B, 80 (2009)
[90] Phys. Rev. Lett., 107 (2011)
[91] Phys. Rev. B, 86 (2012)
[92] J. Phys. Condens. Matter, 21 (2009)
[93] J. Phys. Soc. Jpn., 79 (2010)
[94] Phys. Rev. B, 82 (2010)
[95] Phys. Rev. B, 88 (2013)
[96] Phys. Rev. B, 88 (2013)
[97] Phys. Rev. Lett., 17 (1966), p. 433
[98] Phys. Rev. B, 69 (2004)
[99] Phys. Rev. B, 75 (2007)
[100] Ann. Phys., 193 (1989), p. 206
[101] Phys. Rev. B, 80 (2009) (Erratum Phys. Rev. B, 80, 2009, 104511)
[102] Phys. Rev. B, 82 (2010)
[103] Science, 336 (2012), p. 563
[104] Symmetry, 4 (2012), p. 251
[105] Phys. Rev. Lett., 108 (2012)
[106] Phys. Rev. B, 89 (2014)
[107] arXiv
|[108] Phys. Rev. B, 84 (2011)
[109] Nat. Phys., 10 (2014), p. 845
[110] Nat. Mater., 10 (2011), p. 932
[111] Phys. Rev. B, 85 (2012)
[112] Phys. Rev. Lett., 109 (2012)
[113] arXiv
|[114] Phys. Rev. B, 79 (2009)
[115] Phys. Rev. B, 78 (2008)
[116] Phys. Rev. Lett., 103 (2009)
[117] Phys. Rev. B, 79 (2009)
[118] Phys. Rev. Lett., 104 (2010)
[119] Phys. Rev. B, 82 (2010)
[120] Phys. Rev. B, 88 (2013)
[121] Phys. Rev. B, 81 (2010)
[122] Phys. Rev. Lett., 112 (2014)
[123] Phys. Rev. Lett., 109 (2012)
[124] Phys. Rev. Lett., 103 (2009)
[125] J. Phys. Soc. Jpn., 77 (2008)
[126] Sci. Rep., 4 (2014), p. 7292
[127] Phys. Rev. B, 88 (2013)
[128] C. R. Physique, 17 (2016) no. 1–2, pp. 140-163 ( this issue )
[129] C. R. Physique, 17 (2016) no. 1–2, pp. 90-112 ( this issue )
[130] Phys. Rev. Lett., 101 (2008)
[131] Phys. Rev. B, 77 (2008)
[132] Phys. Rev. B, 79 (2009)
[133] Nat. Phys., 7 (2011), p. 485
[134] Nat. Phys., 8 (2012), p. 709
[135] Phys. Rev. Lett., 101 (2008)
[136] arXiv
|[137] Phys. Rev. Lett., 101 (2008)
[138] Phys. Rev. B, 81 (2010)
[139] Europhys. Lett., 91 (2010), p. 37006
[140] Europhys. Lett., 85 (2009), p. 37005
[141] Nat. Phys. (2015) | DOI
[142] Phys. Rev. B, 79 (2009)
[143] Phys. Rev. B, 79 (2009)
[144] Europhys. Lett., 93 (2011), p. 57003
[145] Phys. Rev. B, 83 (2011)
[146] Phys. Rev. B, 109 (2012), pp. 349-352
[147] Phys. Rev. Lett., 107 (2011)
[148] Phys. Rev. B, 82 (2010)
[149] Science, 337 (2012), p. 1314
[150] et al. | arXiv
[151] Phys. Rev., 85 (2012)
[152] arXiv
|[153] Phys. Rev. Lett., 110 (2013)
[154] Nat. Phys., 10 (2014), p. 97
[155] arXiv
|[156] Phys. Rev. Lett., 111 (2013)
[157] Phys. Rev. B, 91 (2015)
[158] Phys. Rev. Lett., 113 (2014)
[159] Phys. Rev., 121 (1961), p. 1050
[160] Phys. Rev. B, 80 (2009)
[161] Phys. Rev. X, 4 (2014)
[162] arXiv
, 2014 |[163] Phys. Rev. B, 79 (2009)
[164] Phys. Rev. B, 87 (2013)
[165] Nat. Mater., 14 (2014), p. 210
[166] Phys. Rev. Lett., 114 (2015)
[167] Phys. Rev. Lett., 102 (2009)
[168] arXiv
, 2015 (arXiv e-prints) |[169] Phys. Rev. B, 91 (2015)
[170] arXiv
, 2015 (arXiv e-prints) |[171] Nat. Mater., 8 (2009), p. 630
[172] Nat. Phys., 8 (2012), p. 309
[173] et al. Sci. Rep., 4 (2014), p. 4109
[174] Proc. Natl. Acad. Sci. USA, 111 (2014), p. 16309
[175] Phys. Rev. Lett., 113 (2014)
[176] Phys. Rev. B, 89 (2014)
[177] Phys. Rev. B, 90 (2014)
[178] Phys. Rev. B, 91 (2015)
[179] Phys. Rev. B, 91 (2015)
[180] arXiv
|[181] arXiv
|[182] Phys. Rev. B, 90 (2014)
[183] arXiv
|[184] arXiv
|[185] arXiv
|[186] Phys. Rev. Lett., 101 (2008)
[187] J. Phys. Conf. Ser., 449 (2013) no. 012025 (others?)
[188] et al. Europhys. Lett., 106 (2011), p. 273
[189] Europhys. Lett., 93 (2011), p. 57003
[190] Phys. Rev. B, 84 (2011)
[191] Phys. Rev. B, 88 (2013)
[192] et al. Phys. Rev. B, 107 (2011)
[193] et al. Phys. Rev. B, 85 (2012)
[194] Phys. Rev. B, 88 (2013)
[195] arXiv
|[196] et al. Chin. Phys. Lett., 29 (2012)
[197] et al. Nat. Mater., 12 (2013), p. 605
[198] arXiv
(unpublished) |[199] et al. Nat. Commun., 5 (2014), p. 5047
[200] Phys. Rev. B, 89 (2014)
[201] Phys. Rev. B, 89 (2014)
[202] et al. Nature, 515 (2014), p. 245
[203] arXiv
|[204] J. Appl. Phys., 115 (2014)
[205] New J. Phys., 17 (2015)
[206] Phys. Rev. B, 86 (2012)
[207] arXiv
|[208] New J. Phys., 16 (2014)
[209] arXiv
|[210] arXiv
|[211] Nat. Mater., 12 (2013), p. 15
[212] J. Am. Chem. Soc., 136 (2014), p. 630
[213] arXiv
(unpublished) |[214] Physica C, 504 (2014), p. 8
[215] Sci. Rep., 2 (2012), p. 426
[216] Eur. Phys. J. B, 85 (2012), p. 279
[217] J. Phys. Condens. Matter, 24 (2012), p. 382202
[218] Phys. Rev. B, 91 (2015)
[219] Nat. Mater., 14 (2015), p. 325
[220] arXiv
|[221] arXiv
|[222] et al. Nat. Mater., 12 (2013), p. 605
[223] Nat. Commun., 6 (2015), p. 6056
[224] arXiv
|[225] arXiv
|[226] Sov. Phys. JETP, 13 (1961), p. 1018
[227] Phys. Rev. B, 84 (2011)
[228] Phys. Rev. Lett., 102 (2009)
[229] Phys. Rev. Lett., 84 (2000), p. 4445
[230] Phys. Rev. B, 85 (2012)
[231] Phys. Rev. Lett., 108 (2012)
[232] arXiv
|[233] arXiv
|[234] Phys. Rev. B, 53 (1996), p. 2835
[235] J. Phys. Condens. Matter, 81 (2010) no. 10, p. 425702
[236] arXiv
|[237] Phys. Rev. B, 88 (2013)
[238] Phys. Rev. Lett., 112 (2014)
[239] Phys. Rev. X, 3 (2013)
[240] Phys. Rev. B, 89 (2014)
[241] Phys. Rev. X, 2 (2012)
[242] Phys. Rev. Lett., 63 (1989), p. 2144
[243] Phys. Rev. Lett., 67 (1991), p. 370
[244] Phys. Rev. B, 45 (1992), p. 7418
[245] Phys. Rev. Lett., 109 (2012)
[246] arXiv
, 2014 |[247] arXiv
|[248] Ann. Phys., 523 (2011), p. 8
[249] Phys. Rev. B, 88 (2013)
[250] Phys. Rev. B, 90 (2014)
[251] Phys. Rev. Lett., 114 (2015)
[252] J. Low Temp. Phys., 126 (2002), p. 881
[253] Rev. Mod. Phys., 78 (2006), p. 373
[254] Rev. Mod. Phys., 81 (2009), p. 45
[255] Phys. Rev., 131 (1963), p. 563
[256] Phys. Rev. B, 54 (1996), p. 3489
[257] Phys. Rev. B, 55 (1997), p. 15146
[258] Phys. Rev. B, 60 (1999), p. 13062
[259] Sov. Phys. JETP, 39 (1960), p. 1781
[260] Phys. Rev. B, 78 (2008)
[261] Phys. Rev. B, 78 (2008)
[262] New J. Phys., 77 (2008), p. 113710
[263] Phys. Rev. B, 79 (2009)
[264] Phys. Rev. Lett., 103 (2009)
[265] Phys. Rev. B, 85 (2012)
[266] et al. New J. Phys., 12 (2010)
[267] et al. Phys. Rev. B, 82 (2010)
[268] et al. Phys. Rev. B, 81 (2010)
[269] Phys. Rev. B, 87 (2013)
[270] Phys. Rev. X, 4 (2014)
[271] et al. J. Phys. Conf. Ser., 449 (2013) | DOI
[272] Nat. Commun., 5 (2014), p. 5657
[273] Phys. Rev. B, 90 (2014)
[274] Phys. Rev. B, 82 (2010)
[275] Phys. Rev. B, 87 (2013)
[276] Phys. Rev. Lett., 113 (2014)
[277] Phys. Rev. Lett., 99 (2007)
[278] Phys. Rev. B, 89 (2014)
[279] Phys. Rev. Lett., 87 (2001)
[280] Phys. Rev. B, 86 (2012)
[281] Phys. Rev. B, 86 (2012)
[282] Nat. Commun., 4 (2013), p. 3010
[283] J. Phys. Soc. Jpn., 79 (2010)
[284] Phys. Rev. B, 88 (2013)
[285] Europhys. Lett., 101 (2013), p. 57002
[286] Nat. Phys., 11 (2015), p. 543
[287] Phys. Rev. B, 84 (2011)
[288] Physica C, 385 (2003), p. 49
[289] Phys. Rev. B, 79 (2009)
[290] Science, 275 (1997), p. 1764
[291] arXiv
|[292] Phys. Rev. Lett., 114 (2015)
[293] Phys. Rev. B, 68 (2003)
[294] Phys. Rev. B, 73 (2006)
[295] Phys. Rev. B, 78 (2008)
[296] Science, 323 (2009), p. 923
[297] Phys. Rev. B, 81 ( May 2010 )
[298] Phys. Rev. B, 82 (2010)
[299] Phys. Rev. B, 80 (2009)
[300] Introduction to Superconductivity, McGraw-Hill, New York, 1996
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