Topological Excitations in Neutral–Ionic Transition Systems
Abstract
:1. Introduction
2. Topological Excitations in Neutral–Ionic Transition Systems
2.1. Neutral–Ionic Transition Material TTF-CA
2.2. Types of Topological Excitations in Neutral–Ionic Transition Systems
3. Revisited Pressure–Temperature Phase Diagram of TTF-CA
3.1. Previous Phase Diagram
3.2. Revisited Phase Diagram: Ionic Paraelectric Phase Hosting Dimer-Liquid State
4. Experimental Evidence for Mobile Topological Excitations Emerging in TTF-CA
4.1. Magnetism in the Ionic Paraelectric Phase: Spin Soliton
4.2. Electrical Conductivity in the Neutral–Ionic Crossover Region: Neutral–Ionic Domain Wall
- (i).
- (ii).
- The anisotropy of the charge transport was evaluated by measuring the conductivity along the three crystal axes to reveal the nature of unconventional charge carriers.
- (iii).
- We measured the electrical conductivity under finely tuned pressures with a Manganin wire used as a pressure gauge to monitor accurate pressure values near the NI crossover, which allowed us to estimate the activation energy from the conductivity profile along the inclined line parallel to the NI crossover line in the P-T plane, not at a fixed pressure.
4.3. Binding Transition of Solitons upon Space-Inversion Symmetry-Breaking Ferroelectric Order
5. Summary
- (i).
- The revisited pressure–temperature phase diagram contains the paraelectric ionic (Ipara) phase extended in the high-pressure region up to 35 kbar. The N-to-Ipara phase boundary is a crossover, not a phase transition. The Ipara phase hosts the dimer-liquid state, providing a chance for the emergence of mobile NIDWs near the N-to-Ipara crossover and solitons in the Ipara phase.
- (ii).
- In the Ipara phase, spin solitons are thermally excited as mobile boundaries dividing fluctuating dimer domains in 1D chains and contribute to the anomalous topological charge transport in cooperation with the NIDW.
- (iii).
- Near the N-to-Ipara crossover, mobile NIDWs with topological charges carry 1D-confined large electrical conduction in cooperation with spin solitons. This is the first demonstration of the topological charge transport carried by NIDWs and spin solitons in the NI transition system.
- (iv).
- In the 3D ferroelectric ordered (Iferro) phase, spin solitons and charge solitons that are free in the Ipara phase undergo a binding transition to form two-component composite pairings: neutral spin soliton pairs and polaronic spin-soliton–charge-soliton pairs. The polaronic pairs carry magnetism and electrical conduction with the assistance of Peierls-coupled optical phonons.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
- Kosterlitz, J.M.; Thouless, D.J. Ordering, metastability and phase transitions in two-dimensional systems. J. Phys. C Solid State Phys. 1973, 6, 1181–1203. [Google Scholar] [CrossRef]
- Thouless, D.J.; Kohmoto, M.; Nightingale, M.P.; Nijs, M. den Quantized Hall conductance in a two dimensional periodic potential. Phys. Rev. Lett. 1982, 49, 405–408. [Google Scholar] [CrossRef] [Green Version]
- Heeger, A.J.; Kivelson, S.; Schrieffer, J.R.; Su, W.P. Solitons in conducting polymers. Rev. Mod. Phys. 1988, 60, 781–850. [Google Scholar] [CrossRef]
- Wen, X.G. Topological orders and edge excitations in fractional quantum Hall states. Adv. Phys. 1995, 44, 405–473. [Google Scholar] [CrossRef] [Green Version]
- Brazovskii, S. Ferroelectricity and Charge Ordering in Quasi One-Dimensional Organic Conductors. In The Physics of Organic Superconductors and Conductors; Lebed, A., Ed.; Springer: Berlin/Heidelberg, Germany, 2008; pp. 313–355. [Google Scholar]
- Hasan, M.Z.; Kane, C.L. Colloquium: Topological insulators. Rev. Mod. Phys. 2010, 82, 3045–3067. [Google Scholar] [CrossRef] [Green Version]
- Nagaosa, N. Theory of neutral-ionic transition in organic crystals. III. Effect of the electron-lattice interaction. J. Phys. Soc. Jpn. 1986, 55, 2754–2764. [Google Scholar] [CrossRef]
- Soos, Z.G.; Painelli, A. Metastable domains and potential energy surfaces in organic charge-transfer salts with neutral-ionic phase transitions. Phys. Rev. B 2007, 75, 155119. [Google Scholar] [CrossRef]
- Fukuyama, H.; Ogata, M. Solitons in the crossover between band insulator and Mott insulator: Application to TTF-Chloranil under pressure. J. Phys. Soc. Jpn. 2016, 85, 023702. [Google Scholar] [CrossRef] [Green Version]
- Tsuchiizu, M.; Yoshioka, H.; Seo, H. Phase competition, solitons, and domain walls in neutral-ionic transition systems. J. Phys. Soc. Jpn. 2016, 85, 104705. [Google Scholar] [CrossRef] [Green Version]
- Mitani, T.; Saito, G.; Tokura, Y.; Koda, T. Soliton formation at the neutral-to-ionic phase transition in the mixed-stack charge-transfer crystal tetrathiafulvalene-p-chloranil. Phys. Rev. Lett. 1984, 53, 842–845. [Google Scholar] [CrossRef]
- Mitani, T.; Kaneko, Y.; Tanuma, S.; Tokura, Y.; Koda, T.; Saito, G. Electric conductivity and phase diagram of a mixed-stack charge-transfer crystal: Tetrathiafulvalene-p-chloranil. Phys. Rev. B 1987, 35, 427–429. [Google Scholar] [CrossRef] [PubMed]
- Tokura, Y.; Okamoto, H.; Koda, T.; Mitani, T.; Saito, G. Nonlinear electric transport and switching phenomenon in the mixed-stack charge-transfer crystal tetrathiafulvalene-p-chloranil. Phys. Rev. B 1988, 38, 2215–2218. [Google Scholar] [CrossRef] [PubMed]
- Okamoto, H.; Komatsu, T.; Iwasa, Y.; Koda, T.; Tokura, Y.; Koshihara, S.; Mitani, T.; Saito, G. Dynamical aspects of neutral-ionic phase transition in organic charge-transfer complex crystals. Synth. Met. 1988, 27, 189–196. [Google Scholar] [CrossRef]
- Okamoto, H.; Mitani, T.; Tokura, Y.; Koshihara, S.; Komatsu, T.; Iwasa, Y.; Koda, T.; Saito, G. Anomalous dielectric response in tetrathiafulvalene-p-chloranil as observed in temperature- and pressure-induced neutral-to-ionic phase transition. Phys. Rev. B 1991, 43, 8224–8232. [Google Scholar] [CrossRef] [PubMed]
- Takehara, R.; Sunami, K.; Iwase, F.; Hosoda, M.; Miyagawa, K.; Miyamoto, T.; Okamoto, H.; Kanoda, K. Revisited phase diagram on charge instability and lattice symmetry breaking in the organic ferroelectric TTF-QCl4. Phys. Rev. B 2018, 98, 054103. [Google Scholar] [CrossRef] [Green Version]
- Sunami, K.; Nishikawa, T.; Miyagawa, K.; Horiuchi, S.; Kato, R.; Miyamoto, T.; Okamoto, H.; Kanoda, K. Evidence for solitonic spin excitations from a charge-lattice-coupled ferroelectric order. Sci. Adv. 2018, 4, eaau7725. [Google Scholar] [CrossRef] [Green Version]
- Takehara, R.; Sunami, K.; Miyagawa, K.; Miyamoto, T.; Okamoto, H.; Horiuchi, S.; Kato, R.; Kanoda, K. Topological charge transport by mobile dielectric-ferroelectric domain walls. Sci. Adv. 2019, 5, eaax8720. [Google Scholar] [CrossRef] [Green Version]
- Sunami, K.; Takehara, R.; Katougi, A.; Miyagawa, K.; Horiuchi, S.; Kato, R.; Miyamoto, T.; Okamoto, H.; Kanoda, K. Fate of soliton matter upon symmetry-breaking ferroelectric order. Phys. Rev. B 2021, 103, 134112. [Google Scholar] [CrossRef]
- McConnell, H.M.; Hoffman, B.M.; Metzger, R.M. Charge transfer in molecular crystals. Proc. Natl. Acad. Sci. USA 1965, 53, 46–50. [Google Scholar] [CrossRef] [Green Version]
- Torrance, J.B.; Vazquez, J.E.; Mayerle, J.J.; Lee, V.Y. Discovery of a neutral-to-ionic phase transition in organic materials. Phys. Rev. Lett. 1981, 46, 253–257. [Google Scholar] [CrossRef]
- Buron-Le Cointe, M.; Collet, E.; Toudic, B.; Czarnecki, P.; Cailleau, H. Back to the structural and dynamical properties of neutral-ionic phase transitions. Crystals 2017, 7, 285. [Google Scholar] [CrossRef] [Green Version]
- Torrance, J.B.; Girlando, A.; Mayerle, J.J.; Crowley, J.I.; Lee, V.Y.; Batail, P.; LaPlaca, S.J. Anomalous nature of neutral-to-ionic phase transition in tetrathiafulvalene-chloranil. Phys. Rev. Lett. 1981, 47, 1747–1750. [Google Scholar] [CrossRef]
- Tokura, Y.; Koda, T.; Mitani, T.; Saito, G. Neutral-to-ionic transition in tetrathiafulvalene-p-chloranil as investigated by optical reflection spectra. Solid State Commun. 1982, 43, 757–760. [Google Scholar] [CrossRef]
- Girlando, A.; Marzola, F.; Pecile, C.; Torrance, J.B. Vibrational spectroscopy of mixed stack organic semiconductors: Neutral and ionic phases of tetrathiafulvalene–chloranil (TTF–CA) charge transfer complex. J. Chem. Phys. 1983, 79, 1075–1085. [Google Scholar] [CrossRef]
- Dressel, M.; Peterseim, T. Infrared investigations of the neutral-ionic phase transition in TTF-CA and its dynamics. Crystals 2017, 7, 17. [Google Scholar] [CrossRef] [Green Version]
- Masino, M.; Castagnetti, N.; Girlando, A. Phenomenology of the neutral-ionic valence instability in mixed stack charge-transfer crystals. Crystals 2017, 7, 108. [Google Scholar] [CrossRef] [Green Version]
- Kagawa, F.; Horiuchi, S.; Tokura, Y. Quantum phenomena emerging near a ferroelectric critical point in a donor–acceptor organic charge-transfer complex. Crystals 2017, 7, 106. [Google Scholar] [CrossRef] [Green Version]
- Morimoto, T.; Miyamoto, T.; Okamoto, H. Ultrafast electron and molecular dynamics in photoinduced and electric-field-induced neutral–ionic transitions. Crystals 2017, 7, 132. [Google Scholar] [CrossRef] [Green Version]
- D’Avino, G.; Painelli, A.; Soos, Z.G. Modeling the neutral-ionic transition with correlated electrons coupled to soft lattices and molecules. Crystals 2017, 7, 144. [Google Scholar] [CrossRef] [Green Version]
- Tokura, Y.; Okamoto, H.; Koda, T.; Mitani, T.; Saito, G. Pressure-induced neutral-to-ionic phase transition in TTF-p-chloranil studied by infrared vibrational spectroscopy. Solid State Commun. 1986, 57, 607–610. [Google Scholar] [CrossRef]
- Girlando, A.; Pecile, C.; Brillante, A.; Syassen, K. Neutral-ionic interface in mixed stack charge transfer compounds: Pressure induced ionic phase of tetrathiafulvalene-chloranil (TTF-CA). Solid State Commun. 1986, 57, 891–896. [Google Scholar] [CrossRef]
- Horiuchi, S.; Okimoto, Y.; Kumai, R.; Tokura, Y. Anomalous valence fluctuation near a ferroelectric transition in an organic charge-transfer complex. J. Phys. Soc. Jpn. 2000, 69, 1302–1305. [Google Scholar] [CrossRef]
- Matsuzaki, H.; Takamatsu, H.; Kishida, H.; Okamoto, H. Valence fluctuation and domain-wall dynamics in pressure-induced neutral-to-ionic phase transition of organic charge-transfer crystal. J. Phys. Soc. Jpn. 2005, 74, 2925–2928. [Google Scholar] [CrossRef]
- Dengl, A.; Beyer, R.; Peterseim, T.; Ivek, T.; Untereiner, G.; Dressel, M. Evolution of ferroelectricity in tetrathiafulvalene-p-chloranil as a function of pressure and temperature. J. Chem. Phys. 2014, 140, 244511. [Google Scholar] [CrossRef] [Green Version]
- Lemée-Cailleau, M.H.; Le Cointe, M.; Cailleau, H.; Luty, T.; Moussa, F.; Roos, J.; Brinkmann, D.; Toudic, B.; Ayache, C.; Karl, N. Thermodynamics of the neutral-to-ionic transition as condensation and crystallization of charge-transfer excitations. Phys. Rev. Lett. 1997, 79, 1690–1693. [Google Scholar] [CrossRef]
- Le Cointe, M.; Lemée-Cailleau, M.H.; Cailleau, H.; Toudic, B.; Toupet, L.; Heger, G.; Moussa, F.; Schweiss, P.; Kraft, K.H.; Karl, N. Symmetry breaking and structural changes at the neutral-to-ionic transition in tetrathiafulvalene-p-chloranil. Phys. Rev. B 1995, 51, 3374–3386. [Google Scholar] [CrossRef]
- Kanai, Y.; Tani, M.; Kagoshima, S.; Tokura, Y.; Koda, T. X-ray evidence for the molecular dimerization in TTF-chloranil. Synth. Met. 1984, 10, 157–160. [Google Scholar] [CrossRef]
- Tokura, Y.; Kaneko, Y.; Okamoto, H.; Tanuma, S.; Koda, T.; Mitani, T.; Saito, G. Spectroscopic study of the neutral-to-ionic phase transition in TTF-Chloranil. Mol. Cryst. Liq. Cryst. 1985, 125, 71–80. [Google Scholar] [CrossRef]
- Kobayashi, K.; Horiuchi, S.; Kumai, R.; Kagawa, F.; Murakami, Y.; Tokura, Y. Electronic ferroelectricity in a molecular crystal with large polarization directing antiparallel to ionic displacement. Phys. Rev. Lett. 2012, 108, 237601. [Google Scholar] [CrossRef]
- Giovannetti, G.; Kumar, S.; Stroppa, A.; Van Den Brink, J.; Picozzi, S. Multiferroicity in TTF-CA organic molecular crystals predicted through Ab initio calculations. Phys. Rev. Lett. 2009, 103, 266401. [Google Scholar] [CrossRef] [Green Version]
- Ishibashi, S.; Terakura, K. Exotic ferroelectricity in tetrathiafulvalene-p-chloranil: Anomalous effective charges and a picture in the framework of maximally localized wannier orbitals. J. Phys. Soc. Jpn. 2014, 83, 073702. [Google Scholar] [CrossRef]
- Borisov, V.; Biswas, S.; Li, Y.; Valentí, R. Microscopic modeling of correlated systems under pressure: Representative examples. Phys. Status Solidi B 2019, 256, 1900229. [Google Scholar] [CrossRef]
- Resta, R.; Vanderbilt, D. Theory of Polarization: A Modern Approach. In Physics of Ferroelectrics: A Modern Perspective; Rabe, K.M., Ahn, C.H., Triscone, J.-M., Eds.; Springer: Berlin/Heidelberg, Germany, 2007; pp. 31–68. [Google Scholar]
- King-Smith, R.D.; Vanderbilt, D. Theory of polarization of crystalline solids. Phys. Rev. B 1993, 47, 1651–1654. [Google Scholar] [CrossRef]
- Vanderbilt, D.; King-Smith, R.D. Electric polarization as a bulk quantity and its relation to surface charge. Phys. Rev. B 1993, 48, 4442–4455. [Google Scholar] [CrossRef] [PubMed]
- Resta, R. Macroscopic polarization in crystalline dielectrics: The geometric phase approach. Rev. Mod. Phys. 1994, 66, 899–915. [Google Scholar] [CrossRef]
- Nagaosa, N.; Takimoto, J. Theory of neutral-ionic transition in organic crystals. II. Effect of the intersite Coulomb interaction. J. Phys. Soc. Jpn. 1986, 55, 2745–2753. [Google Scholar] [CrossRef]
- Nagaosa, N. Theory of neutral-ionic transition in organic crystals. IV. Phenomenological viewpoint. J. Phys. Soc. Jpn. 1986, 55, 3488–3497. [Google Scholar] [CrossRef]
- Kagawa, F.; Horiuchi, S.; Matsui, H.; Kumai, R.; Onose, Y.; Hasegawa, T.; Tokura, Y. Electric-field control of solitons in a ferroelectric organic charge-transfer salt. Phys. Rev. Lett. 2010, 104, 227602. [Google Scholar] [CrossRef]
- Kishida, H.; Takamatsu, H.; Fujinuma, K.; Okamoto, H. Ferroelectric nature and real-space observations of domain motions in the organic charge-transfer compound tetrathiafulvalene-p-chloranil. Phys. Rev. B 2009, 80, 205201. [Google Scholar] [CrossRef]
- Buron-Le Cointe, M.; Lemée-Cailleau, M.H.; Cailleau, H.; Ravy, S.; Bérar, J.F.; Rouzière, S.; Elkaïm, E.; Collet, E. One-dimensional fluctuating nanodomains in the charge-transfer molecular system TTF-CA and their first-order crystallization. Phys. Rev. Lett. 2006, 96, 205503. [Google Scholar] [CrossRef]
- Morimoto, T.; Miyamoto, T.; Yamakawa, H.; Terashige, T.; Ono, T.; Kida, N.; Okamoto, H. Terahertz-Field-Induced Large Macroscopic Polarization and Domain-Wall Dynamics in an Organic Molecular Dielectric. Phys. Rev. Lett. 2017, 118, 107602. [Google Scholar] [CrossRef] [PubMed]
- Koshihara, S.; Tokura, Y.; Mitani, T.; Saito, G.; Koda, T. Photoinduced valence instability in the organic molecular compound tetrathiafulvalene-p-chloranil (TTF-CA). Phys. Rev. B 1990, 42, 6853. [Google Scholar] [CrossRef] [PubMed]
- Iwai, S.; Okamoto, H. Ultrafast phase control in one-dimensional correlated electron systems. J. Phys. Soc. Jpn. 2006, 75, 011007. [Google Scholar] [CrossRef]
- Miyashita, N.; Kuwabara, M.; Yonemitsu, K. Electronic and lattice dynamics in the photoinduced ionic-to-neutral phase transition in a one-dimensional extended Peierls–Hubbard model. J. Phys. Soc. Jpn. 2003, 72, 2282–2290. [Google Scholar] [CrossRef] [Green Version]
- Ohmura, S.; Mase, T.; Takahashi, A. Terahertz pulse induced transitions between ionic and neutral phases and electronic polarization reversal in TTF-CA. Phys. Rev. B 2019, 100, 035116. [Google Scholar] [CrossRef]
- Watanabe, Y.; Ando, H.; Takahashi, A.; Tomita, N. Nonadiabatic quantum fluctuations in the neutral ground state of tetrathiafulvalene-p-chloranil. Phys. Rev. B 2019, 100, 205205. [Google Scholar] [CrossRef]
- Miyamoto, T.; Yada, H.; Yamakawa, H.; Okamoto, H. Ultrafast modulation of polarization amplitude by terahertz fields in electronic-type organic ferroelectrics. Nat. Commun. 2013, 4, 2586. [Google Scholar] [CrossRef] [Green Version]
- Takaoka, K.; Kaneko, Y.; Okamoto, H.; Tokura, Y.; Koda, T.; Mitani, T.; Saito, G. Infrared molecular-vibration spectra of tetrathiafulvalene-chloranil crystal at low temperature and high pressure. Phys. Rev. B 1987, 36, 3884–3887. [Google Scholar] [CrossRef]
- Luty, T.; Cailleau, H.; Koshihara, S.; Collet, E.; Takesada, M.; Lemée-Cailleau, M.H.; Cointe, M.B.-L.; Nagaosa, N.; Tokura, Y.; Zienkiewicz, E.; et al. Static and dynamic order of cooperative multi-electron transfer. Europhys. Lett. 2002, 59, 619–625. [Google Scholar] [CrossRef]
- Metzger, R.M.; Torrance, J.B. Role of the madelung energy in the neutral-ionic phase transition of Tetrathiafulvalene Chloranil. J. Am. Chem. Soc. 1985, 107, 117–121. [Google Scholar] [CrossRef]
- Okamoto, H.; Koda, T.; Tokura, Y.; Mitani, T.; Saito, G. Pressure-induced neutral-to-ionic phase transition in organic charge-transfer crystals of tetrathiafulvalene-p-benzoquinone derivatives. Phys. Rev. B 1989, 39, 10693–10701. [Google Scholar] [CrossRef] [PubMed]
- Masino, M.; Girlando, A.; Brillante, A. Intermediate regime in pressure-induced neutral-ionic transition in tetrathiafulvalene-chloranil. Phys. Rev. B 2007, 76, 064114. [Google Scholar] [CrossRef] [Green Version]
- Kishine, J.; Luty, T.; Yonemitsu, K. Ferroelectric phase transition, ionicity condensation, and multicriticality in charge-transfer organic complexes. Phys. Rev. B 2004, 69, 075115. [Google Scholar] [CrossRef] [Green Version]
- Gourdji, M.; Guibé, L.; Péneau, A.; Gallier, J.; Toudic, B.; Cailleau, H. 35Cl NQR observation of the neutral-to-ionic phase transition in tetrathiafulvalene-p-chloranil. Solid State Commun. 1991, 77, 609–612. [Google Scholar] [CrossRef]
- Gallier, J.; Toudic, B.; Delugeard, Y.; Cailleau, H.; Gourdji, M.; Peneau, A.; Guibe, L. Chlorine-nuclear-quadrupole-resonance study of the neutral-to-ionic transition in tetrathiafulvalene-chloranil. Phys. Rev. B 1993, 47, 11688. [Google Scholar] [CrossRef]
- Koukoulas, A.A.; Whitehead, M.A. Observations in nuclear quadrupole resonance frequency temperature dependence. Chem. Phys. Lett. 1990, 167, 379–382. [Google Scholar] [CrossRef]
- Yoshinari, Y.; Maniwa, Y.; Takahashi, T.; Mizoguchi, K.; Mitani, T. 1H-NMR studies of neutral-ionic transition in TTF-p-Chloranil. Synth. Met. 1987, 19, 521–526. [Google Scholar] [CrossRef]
- Toudic, B.; Gallier, J.; Boumaza, M.; Cailleau, H. Proton spin-lattice relaxation study of the neutral-to-ionic transition in TTF-chloranil. J. Phys. Fr. 1990, 51, 1671–1678. [Google Scholar] [CrossRef] [Green Version]
- Barthel, E.; Quiron, G.; Wzietek, P.; Jerome, D.; Christensen, J.; Bechgaard, K. NMR in commensurate and incommensurate spin density waves. Europhys. Lett. 1993, 21, 87–92. [Google Scholar] [CrossRef]
- Fujiyama, S.; Nakamura, T. Redistribution of electronic charges in spin-Peierls state in (TMTTF)2AsF6 observed by 13C NMR. J. Phys. Soc. Jpn. 2006, 75, 014705. [Google Scholar] [CrossRef] [Green Version]
- Katan, C. First-principles study of the structures and vibrational frequencies for Tetrathiafulvalene TTF and TTF-d4 in different oxidation states. J. Phys. Chem. A 1999, 103, 1407–1413. [Google Scholar] [CrossRef]
- Bonner, J.C.; Fisher, M.E. Linear magnetic chains with anisotropic coupling. Phys. Rev. 1964, 135, A640. [Google Scholar] [CrossRef] [Green Version]
- Estes, W.E.; Gavel, D.P.; Hatfield, W.E.; Hodgson, D.J. Magnetic and structural characterization of dibromo- and dichlorobis(thiazole)copper(II). Inorg. Chem. 1978, 17, 1415–1421. [Google Scholar] [CrossRef]
- Sachdev, S. NMR relaxation in half-integer antiferromagnetic spin chains. Phys. Rev. B 1994, 50, 13006–13008. [Google Scholar] [CrossRef] [Green Version]
- Takigawa, M.; Motoyama, N.; Eisaki, H.; Uchida, S. Dynamics in the S = 1/2 one-dimensional antiferromagnet Sr2CuO3 via 63Cu NMR. Phys. Rev. Lett. 1996, 76, 4612–4615. [Google Scholar] [CrossRef]
- Devreux, F. Nuclear relaxation in one-dimensional Hubbard systems. Phys. Rev. B 1976, 13, 4651–4657. [Google Scholar] [CrossRef]
- Nechtschein, M.; Devreux, F.; Greene, R.L.; Clarke, T.C.; Street, G.B. One-dimensional spin diffusion in polyacetylene, (CH)x. Phys. Rev. Lett. 1980, 44, 356–359. [Google Scholar] [CrossRef]
- Mizoguchi, K.; Kume, K.; Shirakawa, H. Frequency dependence of electron spin-lattice relaxation rate at 5-450 MHz in pristine trans-polyacetylene—New evidence of one dimensional diffusive motion of electron spin (neutral soliton) ---. Solid State Commun. 1984, 50, 213–218. [Google Scholar] [CrossRef]
- Devreux, F.; Jeandey, C.; Nechtschein, M.; Fabre, J.M.; Giral, L. Electron-proton couplings and local susceptibilities in TTF and TCNQ salts. J. Phys. 1979, 40, 671–677. [Google Scholar] [CrossRef] [Green Version]
- Okamoto, H.; Ishige, Y.; Tanaka, S.; Kishida, H.; Iwai, S.; Tokura, Y. Photoinduced phase transition in tetrathiafulvalene-p-chloranil observed in femtosecond reflection spectroscopy. Phys. Rev. B 2004, 70, 165202. [Google Scholar] [CrossRef]
- Bruinsma, R.; Per Bak, J.B. Torrance Neutral-ionic transitions in organic mixed-stack compounds. Phys. Rev. B 1983, 27, 456–466. [Google Scholar] [CrossRef]
- Karpov, P.; Brazovskii, S. Phase transitions in ensembles of solitons induced by an optical pumping or a strong electric field. Phys. Rev. B 2016, 94, 125108. [Google Scholar] [CrossRef] [Green Version]
- Takehara, R.; Miyagawa, K.; Kanoda, K.; Miyamoto, T.; Matsuzaki, H.; Okamoto, H.; Taniguchi, H.; Matsubayashi, K.; Uwatoko, Y. Electron transport in TTF-CA under high pressures. Physica B 2015, 460, 83–87. [Google Scholar] [CrossRef]
- Orignac, E.; Chitra, R. Mean-field theory of the spin-Peierls transition. Phys. Rev. B 2004, 70, 214436. [Google Scholar] [CrossRef] [Green Version]
- Itoh, Y.; Yasuoka, H. Interrelation between dynamical and static spin gaps in quantum spin systems. J. Phys. Soc. Jpn. 1997, 66, 334–336. [Google Scholar] [CrossRef]
- Abragam, A. The Principles of Nuclear Magnetism; Oxford University Press: Oxford, UK, 1961. [Google Scholar]
- Masino, M.; Girlando, A.; Brillante, A.; Della Valle, R.G.; Venuti, E.; Drichko, N.; Dressel, M. Lattice dynamics of TTF-CA across the neutral-ionic transition. Chem. Phys. 2006, 325, 71–77. [Google Scholar] [CrossRef]
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |
© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
Sunami, K.; Takehara, R.; Miyagawa, K.; Okamoto, H.; Kanoda, K. Topological Excitations in Neutral–Ionic Transition Systems. Symmetry 2022, 14, 925. https://doi.org/10.3390/sym14050925
Sunami K, Takehara R, Miyagawa K, Okamoto H, Kanoda K. Topological Excitations in Neutral–Ionic Transition Systems. Symmetry. 2022; 14(5):925. https://doi.org/10.3390/sym14050925
Chicago/Turabian StyleSunami, Keishi, Ryosuke Takehara, Kazuya Miyagawa, Hiroshi Okamoto, and Kazushi Kanoda. 2022. "Topological Excitations in Neutral–Ionic Transition Systems" Symmetry 14, no. 5: 925. https://doi.org/10.3390/sym14050925