Light Induced High Temperature Superconductivity

Transcription

1 Light Induced High Temperature Superconductivity Daniele Nicoletti Hamburg, Germany SYNQUANT Designer Quantum Systems Out of Equilibrium KITP Santa Barbara November 15 th 016

2 Outline o Resonant excitation of lattice vibrations with femtosecond mid infrared pulses o Light control of interlayer superconducting transport in high T c cuprates o Evidence of light induced superconductivity in thealkali doped fulleride K 3 C 60

3 People Andrea Cavalleri s Group Max Planck Institute for the Structure and Dynamics of Matter, Hamburg Theory Stephen Clark Dieter Jaksch Oxford Alaska Subedi Antoine Georges Paris Samples Matteo Mitrano Roman Mankowsky Cassi Hunt Alice Cantaluppi Bernhard Keimer Hide Takagi Stuttgart Genda Gu Brookhaven Mauro Riccò Parma Michael Först Stefan Kaiser Wanzheng Hu Michele Buzzi

4 Complex solids: many competing phases Collective giant responses to small external perturbations Such responses are often functionally relevant Our goal is to use light to CONTROL materials, induce these phenomena at higher temperatures or modulate and amplify their responses Chemical doping

5 Pump probe experiments time

6 Control at THz frequencies: natural energy scales 1 THz ~ 50 K ~ 4 mev Low energy scales Coherent dynamics No increase in entropy

7 This Talk: Optical control of the lattice mid-ir excitation 30 THz ~ 10 µm 1 5 MV/cm 1 10% unit cell

8 Why? e.g. controlling bond angles in oxides e g Op e g e g Op e g < Insulator Metal

9 Pr 0.7 Ca 0.3 MnO 3 : phonon-driven insulator-to-metal transition Temperature AFI FI CO/OO x M. Rini et al., Nature 449, 7 (007)

10 Lattice displacement? How can optical excitation displace the crystal bond angles?

11 Linear response: no average displacement Q IR 1 V IR Q IR Q IR Q IR IR Aexp( i t)

12 Anharmonic coupling to a second mode V 1 IRQ IR 1 Q AQ IR Q Q IR Q 0 only if Q is a Raman mode M. Först et al., Nature Physics 7, 854 (011) A. Subedi et al., Phys. Rev. B 89, 0301 (014)

13 Lattice displacement via Nonlinear Phononics ( Q Q Q ) AQIR Atomic displacement measured with femtosecond X ray diffraction Q M. Först et al., Sol. State Comm. 169, 4 (013) M. Först et al., Nature Physics 7, 854 (011) A. Subedi et al., Phys. Rev. B 89, 0301 (014)

14 Other examples of lattice control in complex solids Ultrafast Phase Control across Heterostructured Interfaces Phonon induced effective magnetic field A. Caviglia et al., Phys. Rev. Lett. 108, (01) T. Nova et al., Nature Physics, AOP (016) Vibrational control of Hubbard U in organic molecular solid For a review see: M. Först et al., Acc. Chem. Res. 48, 380 (015) R. Mankowsky et al., Rep. Prog. Phys. 79, 6 (016) D. Nicoletti & A. Cavalleri, Adv. Opt. Phot. 8, 401 (016) S. Kaiser et al., Sci. Rep. 4, 383 (014) R. Singla et al., Phys. Rev. Lett. 115, (015)

15 Can we apply this approach to control superconductivity in high T c cuprates?

16 Example #1: The striped cuprate La Eu 0. Sr 0.15 CuO 4 D. Fausti et al., Science 331, 6014 (011)

17 Pumping the in plane Cu O stretching mode 0 THz ~ 15 µm 1 5 MV/cm D. Fausti et al., Science 331, 6014 (011)

18 Probing the interlayer Josephson coupling 0 THz ~ 15 µm 1 5 MV/cm T > T c T < T c 1 Frequency (THz) D. Fausti et al., Science 331, 6014 (011)

19 Light induced superconductivity via stripe melting Transient Josephson Plasma Resonance measured up to T CO = 70 K 1 Frequency (THz) Soft X ray probe reveals stripe melting on the same time scale D. Fausti et al., Science 331, 6014 (011) C. R. Hunt et al., Phys. Rev. B 91, 00505(R) (015) M. Först et al., Phys. Rev. Lett. 11, (014)

20 Light induced superconductivity via stripe melting Transient Josephson Plasma Resonance measured up to T CO = 70 K 1 Frequency (THz) Soft X ray probe reveals stripe melting on the same time scale See also: D. Nicoletti et al., Phys. Rev. B 90, (014) E. Casandruc et al., Phys Rev. B 91, (015) V. Khanna et al., Phys. Rev. B 93, 45 (016)

21 Example #: The bi layer cuprate YBa Cu 3 O 6+x PG T* AFI T ons c SG SC a O Cu Y Ba E. Uykur et al., Phys. Rev. Lett. 11, (014) A. Dubroka et al.,phys. Rev. Lett. 107, (011)

22 Pumping the apical oxygen mode 0 THz ~ 15 µm 1 5 MV/cm PG 1 10% unit cell T* AFI T ons Apical oxygen position correlates with T c at equilibrium SG SC E. Uykur et al., Phys. Rev. Lett. 11, (014) A. Dubroka et al., Phys. Rev. Lett. 107, (011) E. Pavarini et al., Phys. Rev. Lett. 87, (001) C. Weber et al. Phys. Rev. B 8, (010)

23 Probing the inter bilayer transport Equilibrium W. Hu. et al. Nature Materials 13, 705 (014) S. Kaiser et al., Phys. Rev. B 89, (014) C. R. Hunt et al., Phys. Rev. B in press (016)

24 A superconducting like response up to room T Equilibrium Pump Induced W. Hu. et al. Nature Materials 13, 705 (014) S. Kaiser et al., Phys. Rev. B 89, (014) C. R. Hunt et al., Phys. Rev. B in press (016)

25 A superconducting like response up to room T PG Strange Metal T* AFI T ons Lightinduced CDW SG SC W. Hu. et al. Nature Materials 13, 705 (014) S. Kaiser et al., Phys. Rev. B 89, (014) C. R. Hunt et al., Phys. Rev. B in press (016)

26 How does this work? What is the lattice doing?

27 Nonlinear Phononics V 1 IRQ IR 1 Q AQ IR Q Q IR Q 0 only if Q is a Raman mode with A g symmetry Q ( Q Q Q ) AQIR

28 11 A g Raman modes Only four A g modes are coupled strongly with B 1u a 0.8 Ag15 Ag1 Ag9 Ag74 Energy in mev Ag14 Ag39 Ag53 Ag Ag Displacement in pm sqrt(u) 4 6 Ag5 Ag61 Ag63 Alaska Subedi Antoine Georges (Ecole Polytechnique, Paris)!

29 Femtosecond X ray crystallography LCLS I/I in % (0-14) 100K (--11) 100K I/I in % (-04) 100K 0.4 (-11) 100K I/I in % I/I in % time in ps R. Mankowsky et al. Nature 516, 71 (014) time in ps

30 A new, transient crystal structure Lattice Rearrangement Staggered motion of the layers +.1pm.1pm Is this the structure of a room temperature superconductor? R. Mankowsky et al. Nature 516, 71 (014)

31 Similar to external pressure? Light Induced d reduces by > 3% Pressure d reduces by few % 0.0 d (%) -0.5 d x = 6.6 x = 7 R. Mankowsky et al. Nature 516, 71 (014) J. Jorgensen et al. Physica C 171, 93 (1990) Pressure (kbar) 5 6

32 Similar to external pressure? Light Induced T C increases by > 100 K Pressure T C increases by ~10 K 15 YBa Cu 3 O x AFI Lightinduced CDW SC T C (K) x = 6.6 x = 6.8 x = Pressure (kbar) W. Hu. et al. Nature Materials 13, 705 (014) J. G. Huber et al. Phys. Rev. B 41, 8757 (1990) L. E. Schirber et al. Phys. Rev. B 35, 8709 (1987) B. Bucher et al. Journal of Less-Common Metals 164, 165, 0 (1990)

33 Open Questions Role of Charge Order (partial melting) Role of the directly driven IR active mode bilayer Parametric driving M. Först et al., Phys. Rev. B (014) Interbilayer bilayer Decrease phase fluctuations Enhancement of Josephson coupling Theory Z. M. Raines et al., Phys. Rev. B (015) A. Patel & A. Eberlein, Phys. Rev. B 93, (016) Theory R. Höppner et al., Phys. Rev. B (015) J. Okamoto et al., Phys. Rev. Lett. in press (016) S. J. Danny et al., Phys. Rev. Lett (015)

34 There are limitations Transient state isinhomogeneous Equilibrium physics not understood Lightinduced Short lifetime (few picoseconds) AFI CDW SC Is light induced superconductivity specific to cuprates?

35 K 3 C 60 : a 0 K superconductor 3D electronic structure Conventional superconductivity (s wave) High T C (0 K)

36 Equilibrium Superconducting Transition Reflectivity saturates to 1 Gap opening in 1 ( ) Low frequency divergence in ( ) M. Mitrano et al., Nature 530, 461 (016)

37 Mechanism for Superconducting Pairing Undistorted Distorted On ball distortions favor local pairing O. Gunnarsson, Rev. Mod. Phys. 69, 575 (1997) 37

38 Resonant Vibrational Excitation T 1u (4) 170 mev mid IR pump 170 mev M. Mitrano et al., Nature 530, 461 (016) Iwasa et al. PRB 51, 3678 (1995)

39 Vibrational pump / THz probe in K 3 C 60 THz probe ( 10 mev) MIR pump 170 mev M. Mitrano et al., Nature 530, 461 (016)

40 Striking similarity with equilibrium superconductor Equilibrium T < T c Light Induced T > T c M. Mitrano et al., Nature 530, 461 (016) 40

41 Temperature dependence INCREASING TEMPERATURE M. Mitrano et al., Nature 530, 461 (016) 41

42 K 3 C 60 : Stimulated superconductivity? 100 K What is going on?

43 Scenario #1: Modulation of U via Q U coupling? t/ =0 t/ =1/4 t/ =3/4 S. Clark & D. Jaksch, Oxford M. Mitrano et al., Nature 530, 461 (016) Theory: M. Kim et al., Phys. Rev. B 94, (016) D. M. Kennes et al., arxiv: (016) 43

44 Scenario #: Anharmonic coupling to Raman mode? T 1u Q T1uQ Hg H g Electron phonon coupling T 1u (4) 170 mev Dynamical enhancement of pairing? H g (1) 3 mev A. Subedi, Paris M. Mitrano, Nature 530, 461 (016) Theory: M. Sentef et al., Phys. Rev. B 93, (016) M. Knap et al., arxiv: (016) A. Komnik & M. Thorwart, arxiv: (016)

45 People M. Mitrano, A. Cantaluppi, M. Buzzi, R. Mankowsky, W. Hu, M. Först, C. Hunt (now at UC Berkeley), S. Kaiser (now at MPI Stuttgart), A. Subedi (now in Paris), A. Cavalleri MPSD Hamburg M. Chollet, H. Lemke, D. Zhu, J. Turner, W. Schlotter, G. Dakovski, M. Minitti, J. Robinson, J. M. Glownia SLAC National Accelerator Laboratory S. Clark, D. Jaksch Oxford University A. Georges Collège de France Paris H. Takagi, A. Frano, T. Loew, M. Le Tacon, B. Keimer MPI Stuttgart J. Hill, V. Thampy, G. Gu Brookhaven National Laboratory S. Dhesi Diamond Light Source, UK S.O. Mariager, M. Fechner (now at MPSD Hamburg), N. Spaldin PSI & ETH Zürich A. Perucchi, P. Di Pietro, S. Lupi ELETTRA Trieste & University of Rome D. Pontiroli, M. Riccò University of Parma