Εξειδίκευση τύπου :	Άρθρο σε επιστημονικό περιοδικό
Τίτλος:	Magnetic-field-dependent interplay between incoherent and Fermi liquid transport mechanisms in low-dimensional tau-phase organic conductors
Δημιουργός/Συγγραφέας:	Storr, K. Balicas, L. Brooks, J.S. Graf, D. [EL] Παπαβασιλείου Γεώργιος[EN] Papavassiliou, George C.
Εκδότης:	American Physical Society
Ημερομηνία:	2001-07-02
Γλώσσα:	Αγγλικά
ISSN:	0163-1829
DOI:	10.1103/physrevb.64.045107
Περίληψη:	We present an electrical transport study of the 2-dimensional (2D) organic conductor tau-(P-(S,S)-DMEDT-TTF)_2(AuBr)_2(AuBr_2)_y (y = 0.75) at low temperatures and high magnetic fields. The inter-plane resistivity rho_zz increases with decreasing temperature, with the exception of a slight anomaly at 12 K. Under a magnetic field B, both rho_zz and the in-plane resistivity plane rho_xx show a pronounced negative and hysteretic magnetoresistance with Shubnikov de Haas (SdH)oscillations being observed in some (high quality)samples above 15 T. Contrary to the predicted single, star-shaped, closed orbit Fermi surface from band structure calculations (with an expected approximate area of 12.5% of A_FBZ), two fundamental frequencies F_l and F_h are detected in the SdH signal. These orbits correspond to 2.4% and 6.8% of the area of the first Brillouin zone(A_FBZ), with effective masses F_l = 4.0 +/- 0.5 and F_h = 7.3 +/- 0.1. The angular dependence, in tilted magnetic fields of F_l and F_h, reveals the 2D character of the FS and Angular dependent magnetoresistance (AMRO) further suggests a FS which is strictly 2-D where the inter-plane hopping t_c is virtually absent or incoherent. The Hall constant R_xy is field independent, and the Hall mobility increases by a factor of 3 under moderate magnetic fields. Our observations suggest a unique physical situation where a stable 2D Fermi liquid state in the molecular layers are incoherently coupled along the least conducting direction. The magnetic field not only reduces the inelastic scattering between the 2D metallic layers, but it also reveals the incoherent nature of interplane transport in the AMRO spectrum. The apparent ferromagnetism of the hysteretic magnetoresistance remains an unsolved problem.
Τίτλος πηγής δημοσίευσης:	Physical Review B
Τόμος/Κεφάλαιο:	64
Τεύχος:	4
Σελίδες:	045107-1-045107-9
Θεματική Κατηγορία:	[EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry
Κάτοχος πνευματικών δικαιωμάτων:	Τα πνευματικά δικαιώματα ανήκουν στους Συγγραφείς/Δημιουργούς
Ηλεκτρονική διεύθυνση με ανοικτή πρόσβαση (link):	http://arxiv.org/abs/cond-mat/0011529
Ηλεκτρονική διεύθυνση περιοδικού (link) :	http://prb.aps.org/
Σημειώσεις:	Ερευνητικη ομάδα ΕΙΕ: Materials Synthesis and Physical Chemistry The full text is available at: http://arxiv.org/PS_cache/cond-mat/pdf/0011/0011529v1.pdf This is also available in Arxiv: http://arxiv.org/abs/cond-mat/0011529
Εμφανίζεται στις συλλογές:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο