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Page 1: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

The phase diagrams of the

high temperature superconductors

HARVARD

Talk online: sachdev.physics.harvard.edu

Page 2: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Max Metlitski, HarvardMax Metlitski, Harvard

HARVARD

Eun Gook Moon, Harvard

Page 3: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

The cuprate superconductors

Page 4: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Ground state has long-range Néel order

Square lattice antiferromagnet

Page 5: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

The cuprate superconductors

d-wavesuperconductorA

nti

ferr

om

agn

et

Page 6: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

The cuprate superconductors

d-wavesuperconductorA

nti

ferr

om

agn

et

Incommensurate/disordered

antiferromagnetism and charge

order

Page 7: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

The cuprate superconductors

d-wavesuperconductorA

nti

ferr

om

agn

et

Pseudogap

Incommensurate/disordered

antiferromagnetism and charge

order

Page 8: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

The cuprate superconductors

d-wavesuperconductorA

nti

ferr

om

agn

et

StrangeMetal

Pseudogap

Incommensurate/disordered

antiferromagnetism and charge

order

Page 9: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Central ingredients in cuprate phase diagram: antiferromagnetism, superconductivity,

and change in Fermi surface

StrangeMetal

Page 10: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Iron pnictides: a new class of high temperature superconductors

Page 11: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Ishida, Nakai, and HosonoarXiv:0906.2045v1

S. Nandi, M. G. Kim, A. Kreyssig, R. M. Fernandes, D. K. Pratt, A. Thaler, N. Ni,

S. L. Bud'ko, P. C. Canfield, J. Schmalian, R. J. McQueeney, A. I. Goldman,

Physical Review Letters 104, 057006 (2010).

Iron pnictides: a new class of high temperature superconductors

Page 12: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Temperature-doping phase diagram of the iron pnictides:

S. Kasahara, T. Shibauchi, K. Hashimoto, K. Ikada, S. Tonegawa, R. Okazaki, H. Shishido,

H. Ikeda, H. Takeya, K. Hirata, T. Terashima, and Y. Matsuda, Physical Review B 81, 184519 (2010)

Page 13: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Temperature-doping phase diagram of the iron pnictides:

S. Kasahara, T. Shibauchi, K. Hashimoto, K. Ikada, S. Tonegawa, R. Okazaki, H. Shishido,

H. Ikeda, H. Takeya, K. Hirata, T. Terashima, and Y. Matsuda, Physical Review B 81, 184519 (2010)

StrangeMetal

Page 14: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

N. D. Mathur, F. M. Grosche, S. R. Julian, I. R. Walker, D. M. Freye, R. K. W. Haselwimmer,

and G. G. Lonzarich, Nature 394, 39 (1998)

Lower Tc superconductivity in the heavy fermion compounds

CePd2Si2

Page 15: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Lower Tc superconductivity in the heavy fermion compounds

G. Knebel, D. Aoki, and J. Flouquet, arXiv:0911.5223

Page 16: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Can quantum fluctuations near the loss of antiferromagnetism induce higher temperature superconductivity ?

Questions

Page 17: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Can quantum fluctuations near the loss of antiferromagnetism induce higher temperature superconductivity ?

If so, why is there no antiferromagnetism in the cuprates near the point where the superconductivity is strongest ?

Questions

Page 18: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Can quantum fluctuations near the loss of antiferromagnetism induce higher temperature superconductivity ?

If so, why is there no antiferromagnetism in the cuprates near the point where the superconductivity is strongest ?

What is the physics of the strange metal ?

Questions

Page 19: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 20: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 21: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Ground state has long-range Néel order

Square lattice antiferromagnet

Page 22: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Square lattice antiferromagnet

J

J/

Weaken some bonds to induce spin entanglement in a new quantum phase

Page 23: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Square lattice antiferromagnet

J

J/

Ground state is a “quantum paramagnet”with spins locked in valence bond singlets

Page 24: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu
Page 25: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Pressure in TlCuCl3A. Oosawa, K. Kakurai, T. Osakabe, M. Nakamura, M. Takeda, and H. Tanaka, Journal of the Physical Society of Japan, 73, 1446 (2004).

Page 26: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

TlCuCl3

An insulator whose spin susceptibility vanishes exponentially as the temperature T tends to zero.

Page 27: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

TlCuCl3

Quantum paramagnet at

ambient pressure

Page 28: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

TlCuCl3

Neel order under pressureA. Oosawa, K. Kakurai, T. Osakabe, M. Nakamura, M. Takeda, and H. Tanaka, Journal of the Physical Society of Japan, 73, 1446 (2004).

Page 29: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Quantum critical point with non-local entanglement in spin wavefunction

Page 30: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

CFT3

Page 31: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Pressure in TlCuCl3

Page 32: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Christian Ruegg, Bruce Normand, Masashige Matsumoto, Albert Furrer, Desmond McMorrow, Karl Kramer, Hans–Ulrich Gudel, Severian Gvasaliya,

Hannu Mutka, and Martin Boehm, Phys. Rev. Lett. 100, 205701 (2008)

TlCuCl3 with varying pressure

Page 33: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Prediction of quantum field theory

S. Sachdev, arXiv:0901.4103

Page 34: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Pressure in TlCuCl3

Page 35: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

CFT3 at T>0

Pressure in TlCuCl3

Page 36: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

CFT3 at T>0

Pressure in TlCuCl3

Page 37: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 38: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 39: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Central ingredients in cuprate phase diagram: antiferromagnetism, superconductivity,

and change in Fermi surface

StrangeMetal

Page 40: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Fermi surface+antiferromagnetism

Hole states

occupied

Electron states

occupied

Page 41: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Fermi surface+antiferromagnetism

Hole states

occupied

Electron states

occupied

+

Page 42: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Fermi surface+antiferromagnetism

Hole states

occupied

Electron states

occupied

+

Page 43: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

S. Sachdev, A. V. Chubukov, and A. Sokol, Phys. Rev. B 51, 14874 (1995). A. V. Chubukov and D. K. Morr, Physics Reports 288, 355 (1997).

Hole pockets

Electron pockets

Hole-doped cuprates

Page 44: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

S. Sachdev, A. V. Chubukov, and A. Sokol, Phys. Rev. B 51, 14874 (1995). A. V. Chubukov and D. K. Morr, Physics Reports 288, 355 (1997).

Hole pockets

Electron pockets

Hole-doped cuprates

Page 45: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

S. Sachdev, A. V. Chubukov, and A. Sokol, Phys. Rev. B 51, 14874 (1995). A. V. Chubukov and D. K. Morr, Physics Reports 288, 355 (1997).

Hole pockets

Electron pockets

Hole-doped cuprates

Page 46: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

S. Sachdev, A. V. Chubukov, and A. Sokol, Phys. Rev. B 51, 14874 (1995). A. V. Chubukov and D. K. Morr, Physics Reports 288, 355 (1997).

Hole pockets

Electron pockets

Hole-doped cuprates

Fermi surface breaks up at hot spotsinto electron and hole “pockets”

Hole pockets

Page 47: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

S. Sachdev, A. V. Chubukov, and A. Sokol, Phys. Rev. B 51, 14874 (1995). A. V. Chubukov and D. K. Morr, Physics Reports 288, 355 (1997).

Hole pockets

Electron pockets

Hole-doped cuprates

Fermi surface breaks up at hot spotsinto electron and hole “pockets”

Page 48: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Physical Review B 81, 140505(R) (2010)

Suchitra E. Sebastian, N. Harrison, M. M. Altarawneh, Ruixing Liang, D. A.

Bonn, W. N. Hardy, and G. G. Lonzarich

Evidence for small Fermi pockets

Original observation:N. Doiron-Leyraud, C. Proust, D. LeBoeuf, J.

Levallois, J.-B. Bonnemaison, R.

Liang, D. A. Bonn, W. N. Hardy,

and L. Taillefer, Nature 447, 565 (2007)

Page 49: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Theory of quantum criticality in the cuprates

T*

QuantumCritical

Page 50: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Theory of quantum criticality in the cuprates

T*

QuantumCriticalStrangeMetal ?

Page 51: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 52: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 53: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Physical Review B 34, 8190 (1986)

Page 54: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Spin density wave theory in hole-doped cuprates

Page 55: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Spin-fluctuation exchange theory of d-wave superconductivity in the cuprates

Page 56: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

++_

_

Page 57: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Theory of quantum criticality in the cuprates

Page 58: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Theory of quantum criticality in the cuprates

Ar. Abanov, A.V. Chubukov,

and J. Schmalian, Advances in

Physics 52, 119 (2003).

Page 59: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 60: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 61: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Competition between superconductivity (SC) and spin-density wave (SDW) order

Phenomenological quantum theory of competing orders

Page 62: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Competition between superconductivity (SC) and spin-density wave (SDW) order

Phenomenological quantum theory of competing orders

Page 63: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Competition between superconductivity (SC) and spin-density wave (SDW) order

Phenomenological quantum theory of competing orders

Page 64: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Competition between superconductivity (SC) and spin-density wave (SDW) order

Phenomenological quantum theory of competing orders

Page 65: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Competition between superconductivity (SC) and spin-density wave (SDW) order

Phenomenological quantum theory of competing orders

Page 66: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Competition between superconductivity (SC) and spin-density wave (SDW) order

Phenomenological quantum theory of competing orders

Page 67: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Theory of quantum criticality in the cuprates

Page 68: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Theory of quantum criticality in the cuprates

Ar. Abanov, A.V. Chubukov,

and J. Schmalian, Advances in

Physics 52, 119 (2003).

Page 69: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Theory of quantum criticality in the cuprates

Page 70: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Theory of quantum criticality in the cuprates

Page 71: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

T*

Page 72: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

T*

Page 73: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

T*

Quantum oscillations

Quantum oscillations

Page 74: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

T*

Many experiments

have presented

evidence for the predicted

green quantum

phase transition line

from SC to SC+SDW in a magnetic field

Page 75: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu
Page 76: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

G. Knebel, D. Aoki, and J. Flouquet, arXiv:0911.5223

Similar phase diagram for CeRhIn5

Page 77: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Ishida, Nakai, and HosonoarXiv:0906.2045v1

S. Nandi, M. G. Kim, A. Kreyssig, R. M. Fernandes, D. K. Pratt, A. Thaler, N. Ni,

S. L. Bud'ko, P. C. Canfield, J. Schmalian, R. J. McQueeney, A. I. Goldman,

Physical Review Letters 104, 057006 (2010).

Iron pnictides: a new class of high temperature superconductors

Page 78: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 79: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

1. Loss of antiferromagnetism in an insulator Coupled-dimer antiferromagnets and quantum criticality

2. Onset of antiferromagnetism in a metal From large Fermi surfaces to Fermi pockets

3. Unconventional superconductivity Pairing from antiferromagnetic fluctuations

4. Competing orders Phase diagram in a magnetic field

5. Strongly-coupled quantum criticality in metals Fluctuating antiferromagnetism and Fermi surfaces

Outline

Page 80: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Quantum criticality of the onset of antiferromagnetism in a metal

Metal with “large” Fermi surface s

Metal with electron and hole pockets

Page 81: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Quantum criticality of the onset of antiferromagnetism in a metal

Metal with “large” Fermi surface s

Metal with electron and hole pockets

Page 82: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Quantum criticality of the onset of antiferromagnetism in a metal

Metal with “large” Fermi surface s

Metal with electron and hole pockets

Quantum critical theory is strongly-coupled in two (but not higher) spatial dimensions (but not a CFT).

M.A. Metlitski and S. Sachdev, Physical Review B 82, 075128 (2010)

Page 83: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Quantum criticality of the onset of antiferromagnetism in a metal

Metal with “large” Fermi surface s

Metal with electron and hole pockets

Theory has strong (log-squared) instability already at the Fermi energy to superconductivity with sign-changing pairing amplitude near quantum criticality.

M.A. Metlitski and S. Sachdev, Physical Review B 82, 075128 (2010)

Page 84: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Quantum criticality of the onset of antiferromagnetism in a metal

Metal with “large” Fermi surface s

Metal with electron and hole pockets

There is non-Fermi liquid behavior at the QCP not only at hotspots, but on entire Fermi surface.

M.A. Metlitski and S. Sachdev, Physical Review B 82, 075128 (2010)

Page 85: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Can quantum fluctuations near the loss of antiferromagnetism induce higher temperature superconductivity ?

If so, why is there no antiferromagnetism in the cuprates near the point where the superconductivity is strongest ?

What is the physics of the strange metal ?

Questions

Page 86: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Can quantum fluctuations near the loss of antiferromagnetism induce higher temperature superconductivity ?

If so, why is there no antiferromagnetism in the cuprates near the point where the superconductivity is strongest ?

Questions and answers

Yes

What is the physics of the strange metal ?

Page 87: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Can quantum fluctuations near the loss of antiferromagnetism induce higher temperature superconductivity ?

If so, why is there no antiferromagnetism in the cuprates near the point where the superconductivity is strongest ?

Questions and answers

Yes

What is the physics of the strange metal ?

Competition between antiferromagnetism and superconductivity has shifted the antiferromagnetic quantum-critical point (QCP), and shrunk the region of antiferromagnetism. This QCP shift is largest in the cuprates

Page 88: The phase diagrams of the high temperature superconductors HARVARD Talk online: sachdev.physics.harvard.edu

Can quantum fluctuations near the loss of antiferromagnetism induce higher temperature superconductivity ?

If so, why is there no antiferromagnetism in the cuprates near the point where the superconductivity is strongest ?

Questions and answers

Yes

What is the physics of the strange metal ?Proposal: strongly-coupled quantum criticality of fluctuating antiferromagnetism in a metal

Competition between antiferromagnetism and superconductivity has shifted the antiferromagnetic quantum-critical point (QCP), and shrunk the region of antiferromagnetism. This QCP shift is largest in the cuprates