Pseudo-Gap and its Collapse in hole doped Cuprates

Transcription

1 Pseudo-Gap and its Collapse in hole doped Cuprates Alain Sacuto Laboratoire Matériaux et Phénomènes Quantiques Paris-Diderot University SQUAP team: Spectroscopy of QUAsi-Particules Team M. Cazayous Y. Gallais M.A. Méasson Paris, January, 5 Ph-D students S. Benhabib J. Buhot R. Grasset B. Loret P. Massat E. Riccardi C. Toulouse

2 Close collaborators Antoine Georges Collège de France Ecole Polytechnique Dorothée Colson SPEC, CEA, Saclay Marcello Civelli LPS, Orsay Indranil Paul MPQ, Paris Diderot Catherine Pépin, IPhT, CEA, Saclay Genda Gu Mat.Sc.Dpt. BNL

3 Hole-doped cuprate phase diagram T * T- dependence d Knight shift Tem mperatu ure AF state Pseudogap Loss of low energy states at the Fermi level T CDW Field Induced CO T Max c SC UD dome OD Max H. Alloul, et al. PRL W. Warren et al. PRL doping level p

4 signatures of the pseudogap In optical conductivity along the c axis Loss of QSP spectral weight UD- YBa Cu 3 O Tc=63K in the ab-plane Loss of scattering rate UD-YBa Cu 3 O 6.6 Tc=58K 95K 5K 7K C. C.Homes et al. Physica C 54, 65, 995 A.V. Pushkov et al. J.Phys: Cond Matter 8, 49, 996 See also: RMP 77, 5, Basov, Timusk; RMP 83, Basov, Averiit, Van der Marel, Dressel and the Review of R. Lobo, The optical conductivity of HTS, Chap. 3, p. 3, Ed. X. G. Qiu, Woodhead Publishing, Oxford.

5 distincts signatures of the PG in Resistivity Loss of low energy spectral weight upturn in ρ c T* c-axis Bi- optimal doping Loss of scattering rate down shift in ρ ab T* ab plane H. Raffy et al. Physica C

6 distinct doping evolutions of T* along the c-axis and the ab-plane Bi- Bi- T* ab-plane T* c-axis T* ab-plane T* c-axis H. Raffy et al. Physica C T. Usui et al. arxiv: v See also: T. Shibauchi et al. PRL 86, 5764, Does these distinct T*merge or correspond to distinct transitions at low temperature? ab-plane properties deduced from transport, optics, tunnelling... Suggest a QCP, p.9 in Bi- What can we learn from c-axis properties in Bi-?

7 Electronic Raman scattering on Bi- single crystals

8 Bi- Single Crystals. UD OD.3 Bi- T max c=9 K Bi Ca Ba Nor rmalized Susceptibilt ty Bi- OD cyrstals: 5; 56; 58; 63; 7; 78; 83 UD crystals: 5; 68; 7; 78 before cleaving Single crystals from G. Gu and D. Colson OP 9 after cleaving Temperature in K

9 Electronic Raman Scattering in the Normal/SC states Normal metal SC metal Cuprate Bi- ω i q i e-h ω s q s E F + γ γ +Δ k -Δ k Ra aman Inten nsity (arb,un nits) Tc=9 Δ K K Raman Shift cm- Raman shift : ω R = ω i - ω s

10 Raman response for a «d-wave» gap in cuprates Δ( φ) cos( kx ) cos( ky) cos(φ ) Δ π/a k y φ π/a π/a. Bi- OP 9 Anti-Nodes Nodes B geometry B geometry k x π/a χ''(ω) arb. units.8.4 x.5 Anti-Nodal Region Nodal Region Raman vertices: γ AN or γ N Raman Shift cm- See RMP 79, 75, Hackl, Devereaux and Blanc et al. PRB 8, 4456, 9

11 Focus on the Anti-Nodal Raman response Raman vertex at the Anti-Nodes c-axis hopping γ AN ) ( cos( kx ) cos( ky ) t (k) Probing the QSP dynamic at the Anti-Nodes Corresponds to probing the QSP dynamic along the c-axis the Anti-Nodal Raman response should exhibit a loss of spectral weight as in c-axis optical conductivity

12 units ) in arb. χ''bg (ω 6 4 Electronic Raman response at the Anti-Nodes In underdoped cuprate χ' ' Bg ( Bi- UD 75 ω) Bi- UD 75 ω,t) dω ( ar rb. units) χ''bg (ω Raman shift (cm-). Tc 75 χ ' ' B g ) ( ω dω T* > slope just above Tc UD Temperature (K) S. Benhabib, A.S, M.Civelli, I. Paul et al. arxiv:43.76, accepted in PRL 5 ROP 76, 5, 3. A.S. Y. Gallais, M. Cazayous, M. Méasson, D.Colosn et al.

13 K 9 K K 3K 5 4K 5 5K 75 6K 7K 5 8K 3K χ' ' B g Detection of the normal state Pseudogap ( ω ). χ '' B g ( ω ) dω χ' ' B g ( ω ) UD 75 T* UD 75. OD 7. T c K χ ' ' B g ) > slope > Tc 74 ( ω dω T* OD 7. K 9K K K 3K 5K 4K 5 5K 6K 5 7K 3 8K K 85K K 9K 3K K 4K 5K 5K 5K 6K K 7K 5K 75K 3K. UD 85.3 UD 85 OD Tc 85 T* 85. OD 8 OD 8 OD 5..9 Tc 8 > > T* 6 6K K Raman shift (cm - ) Temperature (K) Raman shift (cm - ). Tc OD < slope Tc OD < 3 Temperature (K)

14 Ending Point of the normal state PG in Bi- from the Anti-Nodes Tempera ature (K K) Tc This work doping level p S. Benhabib, A.S. M.Civelli, I. Paul et al. arxiv:43.76, accepted in PRL 5 PG loss s of spe ctral we ight

15 Nebula of T* values from spectroscopy and transport on Bi- only rature in K Tempe 35 Tc Raman Bg Siham et al. T*ARPES (Vishik) T* Tun. BVB. (Dipasupil) 3 T* SIS/SNS (Myakawa-Ozyuzen) T Mag IN (Bourges-Sidis) T MNR K(Ishida) T*ARPES Pb: Bi (Vishik) 5 T*rho c (watanabe) T rho c (Raffy) T* ARPES ( Ding+Kanigel) T* ARPES (Chatterjee) T* MNR SLR (Ishida) Raman Bg Y:Bi (Opel) J doping level p

16 Selection of T* from Anti-Nodes and C-axis 35 Temper rature in K Tc T* Ram. our group T*ARPES (Vishik) T* Tun. BVB. (Dipasupil) il) T* SIS/SNS (Myakawa_Ozyuzen) T Mag NS (Bourges- Sids ) T*ARPES Bi_Pb (Vishik) T*rho c (watanabe). ending of PG doping level p

17 What is happening at p=.?

18 Doping evolution of the A-Nodal/Nodal Raman responses SC state Normal state increase e nits) χ'' ν (ω) (arb.u UD 5 p=.9 T=K AN N OD 7 K UD 5 K OD 7. AN N AN N UD 7. OP 9.6 K K OD 63 K. OD 56 K UD 7 OP 9 K K.3 OD 63. OD 56 K AN N K K doping ω) (arb.units) χ'' ν (ω OD 78 K OD 5 K OD 78 K OD 5 K. > Raman Shift (Δ unit) Raman Shift (Δ unit) Raman Shift (Δ unit) Raman Shift (Δ unit) S. Benhabib, A.S. M.Civelli, I. Paul et al. arxiv:43.76, accepted in PRL 5

19 Doping evolution of the A-N /N integrated intensity ratio Intens sity Ratios (I Bg /I Bg ) I /I N (SC) I AN/I N (N) Bi- vhs p c = doping level p S. Benhabib et al. arxiv:43.76 accepted in PRL 5

20 Doping evolution of the A-N /N integrated intensity ratio g(bg) (ω) N B Inte ensity Rat tios (I Bg /I Bg ) doping evolution of the AB band in Bi p=.6 Bg (AN) Bg (Nod.) - p=.6 p=. 4 I AN /I N (SC) I AN /I N (N) n π/a unit) 6 p=. Bg Bg AN PG depletion 6 p=.9 p=.9 4 Bg Bg ky (i - Node Bg ity ratio I Bg /I intensi AB (N) AB (SC) Bi- vhs p c = energy (in t unit ) kx (in π/a unit) level of doping p doping level p PG dep letion Ma agnitude S. Benhabib et al. arxiv:43.76 accepted in PRL 5

21 Doping evolution of the A-N /N integrated intensity ratio g(bg) (ω) N B Inte ensity Rat tios (I Bg /I Bg ) doping evolution of the AB band in Bi p=.6 Bg (AN) Bg (Nod.) n π/a unit) - p=.6 6 p=. p=. 4 I AN /I N (SC) I AN /I N (N) Bg Bg 6 p=.9 p=.9 4 Bg Bg energy (in t unit ) ky (i - - AN Node Bg ity ratio I Bg /I intensi AB (N) AB (SC) Bi vhs p c =..8 kx (in. π/a unit).6 level of doping p..4 ARPES, A. Kaminski et al. PRB 73, 745,6 BB p=. AB doping level p

22 Doping evolution of the A-N /N integrated intensity ratio Inte ensity Rat tios (I Bg /I Bg ) 6 Bi vhs PG depletion p c = doping level p PG dep letion Ma agnitude The normal state pseudo gap disapears at the Lifshitz transition S. Benhabib et al. arxiv:43.76 accepted in PRL 5

23 How can we explain this coincidence? A-Node hole like Fermi surface electron like Fermi surface ky (in π/a unit t) ky (in π/a unit) - - p=.6 p=. A-Node We remove Quasi-particles from hot Regions associated to strong scattering (AF fluctuations, CDW Mott-related Physics ) So, we loose the PG k x (in π/a unit)

24 Does this Coincidence of the pseudogap closing with a Lifshitz transition is universal? T Bi- 9K T c SC T* vhs p C T LSCO 39K T c SC T* vhs T Bi- K T c SC p p p p C Our study Raman A. Ino et al. ARPES arxiv:43.76 PRB 65, 9454 The location of the PG collapse appears to be material dependent S. Benhabib, A.S, M.Civelli, I. Paul et al. arxiv:43.76 T* p C vhs A. Piriou et al. Tunnelling Nat. Comm. 9

25 Conclusions Probing the QSP at the Anti-Nodes in Bi- by Electronic Raman Scattering allows us to detect the loss of spectral weight due to the PG seen in c-axis data (optics, resistivity,sis) and reveal its collapse at p c =. (.9 detected from ab plane data ) This collapse occurs at a Lifshitz transition This demonstrates that the mecanism that gives rise to the normal state pseudogap at tthe Anti-Nodes tin is sensitive to the FS topology

26 Thank you!