title: Phase transitions, magnetotransport and magnetocaloric effects in a new family of quaternary Ni-Mn-In-Z Heusler alloys.
abstract: The magnetic, magnetotransport, and magnetocaloric properties near compound phase transitions in Ni50Mn35In14Z (Z = In, Ge, Al), and Ni48Co2Mn35In15 Heusler alloys have been studied using VSM and SQUID magnetometers (at magnetic fields (H) up to 5 T), four-probe method (at H = 0.005-1.5 T), and an adiabatic magnetocalorimeter (for H changes up to deltaH = 1.8 T), respectively. The martensitic transformation (MT) is accompanied by large magnetoresistance (up to 70%), a significant change in resistivity (up to 200%), and a sign reversal of the ordinary Hall effect coefficient, all related to a strong change in the electronic spectrum at the MT. The field dependences of the Hall resistance are complex in the vicinity of the MT, indicating a change in the relative concentrations of the austenite and martensite phases at strong fields. Negative and positive changes in adiabatic temperatures of about -2 K and +2 K have been observed in the vicinity of MT and Curie temperatures, respectively, for deltaH = 1.8 T.
authors.affiliation: Faculty of Physics, Moscow State University, Vorob'evy Gory, 119991 Moscow, Russia.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kazakov
authors.forename: Valerii
authors.initials: V
authors.lastname: Prudnikov
authors.forename: Alexander
authors.initials: A
authors.lastname: Granovsky
authors.forename: Nikolai
authors.initials: N
authors.lastname: Perov
authors.forename: Igor
authors.initials: I
authors.lastname: Dubenko
authors.forename: Arjun Kumar
authors.initials: AK
authors.lastname: Pathak
authors.forename: Tapas
authors.initials: T
authors.lastname: Samanta
authors.forename: Shane
authors.initials: S
authors.lastname: Stadler
authors.forename: Naushad
authors.initials: N
authors.lastname: Ali
authors.forename: Arcady
authors.initials: A
authors.lastname: Zhukov
authors.forename: Maxim
authors.initials: M
authors.lastname: Ilyin
authors.forename: Julian
authors.initials: J
authors.lastname: Gonzalez