Co doping enhanced giant magnetocaloric effect in Mn1−xCoxAs films epitaxied on GaAs (001)

Abstract

A giant magnetocaloric effect was found in series of Mn1−xCoxAs films epitaxied on GaAs (001). The maximum magnetic entropy change caused by a magnetic field of 4 T is as large as 25 J/kg K around room temperature, which is about twice the value of pure MnAs film. The observed small thermal hysteresis is more suitable for practical application. Growing of layered Mn1−xCoxAs films with Co concentration changing gradually may draw layered active magnetic regenerator refrigerators closer to practical application. Our experimental result may provide the possibility for the combination of magnetocaloric effect and microelectronic circuitry.

Magnetocaloric effect in epitaxial La0.56Sr0.44MnO3 alloy and digital heterostructures

“…3,4 While the MCE is most frequently studied in bulk materials, there has been some effort recently to explore the MCE in nanoscale materials. [5][6][7][8][9][10][11][12] In Refs. 5 and 6 it was shown that finite size effects can detrimentally impact the magnetic entropy change in Gd/W multilayers.…”

Ferromagnetism and magneto-transport properties of Mn0.92Ca0.08As thin film grown on Al2O3(0001) substrate

“…These values are higher than those of Codoped MnAs (25 J/kgK at 4 T), Fe-doped MnAs (42 J/kgK at 5 T) and comparable to that of Cu-doped MnAs (175 J/kgK at 5 T). [6][7][8][9] …”

“…4 On the other hand, a giant magnetic field-induced uniaxial strain of 0.7% in MnAs is also reported by Cherenko et al 5 Recently, the room temperature giant MCE was also obtained by substitution of Mn by Fe, Co, Cr, and Cu. [6][7][8][9] Cui et al reported that with increasing Si doping in MnAs 1Àx Si x , the thermal hysteresis is decreased to nearly zero (x > 0.06), and the maximum of the magnetic entropy change is maintained above 10 and 5 J/(kgK) at 5 T and 2 T, respectively. 10,11 In addition, they studied the effect of interstitial nitrogen on the phase transition and magnetocaloric behavior of MnAs 1Àx Si x N d (x ¼ 0.03, 0.06, and 0.09).…”

Giant magnetocaloric effect in composites based on polymeric matrix and manganese arsenide

“…In these cases, relatively smaller thermal/magnetic hysteresis than those possessing magnetostructural transition are generally revealed. In numerous materials presenting FOMT, Mn-based intermetallic compounds, such as MnFePAs(Si/Ge) [13,18], MnAs [20,21], Ni-Mn-based [9][10][11], and Mn(Co,Ni)Ge systems [12,14], have extensively been investigated owing to the low cost and higher magnetic moment of Mn atoms, sometimes even 4 µ B per Mn atom [18].…”