Enhancement of Curie temperature in Ga[sub 1-x]Mn[sub x]As/Ga[sub 1-y]Al[sub y]As ferromagnetic heterostructures by Be modulation doping

Wojtowicz, T.; Lim, W. L.; Liu, X.; Dobrowolska, M.; K.#Furdyna, J.; Yu, K. M.; Walukiewicz, W.; Vurgaftman, i.; Meyer, J. R.
November 2003
Applied Physics Letters;11/17/2003, Vol. 83 Issue 20, p4220
Academic Journal
The effect of modulation doping by Be on the ferromagnetic properties of Ga[sub 1-x]Mn[sub x]As is investigated in Ga[sub 1-x]Mn[sub x]As/Ga[sub 1-y]Al[sub y]As heterojunctions and quantum wells. Introducing Be acceptors into the Ga[sub 1-y]Al[sub y]As barriers leads to an increase of the Curie temperature T[sub C] of Ga[sub 1-x]Mn[sub x]As, from 70 K in undoped structures to over 100 K with the modulation doping. This increase is qualitatively consistent with a multiband mean field theory simulation of carrier-mediated ferromagnetism. An important feature is that the increase of T[sub C] occurs only in those structures where the modulation doping is introduced after the deposition of the magnetic layer, but not when the Be-doped layer is grown first. This behavior is expected from the strong sensitivity of Mn interstitial formation to the value of the Fermi energy during growth. © 2003 American Institute of Physics.


Related Articles

  • Magnetization Process near the Curie Temperature of a Ferromagnetic Heusler Alloy CoVGa. Nishihara, H.; Furutani, Y.; Wada, T.; Kanomata, T.; Kobayashi, K.; Kainuma, R.; Ishida, K.; Yamauchi, T. // Journal of Superconductivity & Novel Magnetism;Feb2011, Vol. 24 Issue 1/2, p679 

    The field dependence of the magnetization of a ferromagnetic Heusler alloy CoVGa has been measured close to the Curie temperature of 358 K up to an applied field of 50 kOe. Results for samples with different Curie temperatures of 351 K are also reported. The critical exponent δ has been...

  • Effect of charge carriers on the magnetic properties of the CdCr2Se4 ferromagnetic semiconductor. Vinogradova, G. I.; Anzina, L. V.; Veselago, V. G.; Glushkov, M. V.; Menshchikova, T. N.; Zhukov, É. G. // Physics of the Solid State;May2007, Vol. 49 Issue 5, p912 

    The results of an investigation into how the composition of annealing mixtures influences the Curie temperature of single crystals of the CdCr2Se4 ferromagnetic semiconductor are reported. The mechanism of doping of single crystals is analyzed, and the role played by each of the components of...

  • Magnetic and electrical properties of the ZnGeAs2: Mn chalcopyrite. Koroleva, L. I.; Pavlov, V. Yu.; Zashhirinskiĭ, D. M.; marenkin, S. F.; Varnavskiĭ, S. A.; Szymczak, R.; Dobrovol’skiĭ, V.; Killinskiĭ, L. // Physics of the Solid State;Nov2007, Vol. 49 Issue 11, p2121 

    Doping of the ZnGeAs2 semiconductor with manganese has produced compositions with spontaneous magnetization and high Curie temperatures of up to 367 K for the composition 3.5 wt% Mn. Their magnetic properties are characteristic of spin glasses at temperatures T < T S and magnetic fields H < 11...

  • Room-temperature ferromagnetism in Cu-doped ZnO thin films. Buchholz, D. B.; Chang, R. P. H.; Song, J. H.; Ketterson, J. B. // Applied Physics Letters;8/22/2005, Vol. 87 Issue 8, p082504 

    A series of copper-doped zinc oxide films were grown by pulsed-laser ablation. Films grown under conditions that produced n-type ZnO were nonmagnetic while those grown under conditions that produced p-type were ferromagnetic with a Curie temperature above 350 K. The magnetic moment per copper...

  • Significant suppression of ferromagnetism by hydrostatic pressure in the diluted magnetic semiconductor Sb2-xVxTe3 with x<=0.03. Dyck, J. S.; Mitchell, T. J.; Luciana, A. J.; Quayle, P. C.; Drasˇar, Cˇ.; Losˇtˇák, P. // Applied Physics Letters;9/17/2007, Vol. 91 Issue 12, p122506 

    The authors report on the hydrostatic pressure dependence of the magnetotransport properties of ferromagnetic Sb2-xVxTe3 single crystals with x=0.02–0.03. Pressure significantly increases the free hole concentration in these compounds. In turn, the Curie temperature is suppressed by...

  • Dependence of ferromagnetic properties on conductivity for As-doped p-type (Zn0.93Mn0.07)O layers. Lee, Sejoon; Shon, Yoon; Won Kang, Tae; Yoon, Chong S.; Kim, Eun Kyu; Kim, Deuk Young // Applied Physics Letters;7/14/2008, Vol. 93 Issue 2, p022113 

    The As-doped p-type (Zn0.93Mn0.07)O layers show a strong dependence of their ferromagnetic properties on the hole conductivity that were controlled through the modification of negative background-charge density by changing the oxygen partial pressure during the initial growth stage before As...

  • Ferromagnetic semiconductor (In,Ga,Mn)As with Curie temperature above 100 K. Slupinski, T.; Munekata, H.; Oiwa, A. // Applied Physics Letters;3/4/2002, Vol. 80 Issue 9, p1592 

    We have grown (In[sub y]Ga[sub l-y])[sub 1-x]Mn[sub x]As ferromagnetic semiconductor layers with Mn composition of χ up to 0.13 on InP substrates by molecular beam epitaxy. Near the lattice-matched composition, i.e., y∼0.53, the Curie temperature increases linearly with the...

  • Curie temperature and carrier concentration gradients in epitaxy-grown Ga[sub 1-x]Mn[sub x]As layers. Koeder, A.; Frank, S.; Schoch, W.; Avrutin, V.; Limmer, W.; Thonke, K.; Sauer, R.; Waag, A.; Krieger, M.; Zuern, K.; Ziemann, P.; Brotzmann, S.; Bracht, H. // Applied Physics Letters;5/12/2003, Vol. 82 Issue 19, p3278 

    We report on detailed investigations of the electronic and magnetic properties of ferromagnetic Ga[SUB1-x]Mn[SUBx]As layers, which have been fabricated by low-temperature molecular-beam epitaxy. Superconducting quantum interference device measurements reveal a decrease of the Curie temperature...

  • Magnetization patterns of slave media duplicated by using patterned master media. Sugita, R.; Saito, O.; Muranoi, T.; Nishikawa, M.; Nagao, M. // Journal of Applied Physics;5/15/2002 Part 1, 2 & 3, Vol. 91 Issue 10, p8694 

    A method for the analysis of temperature and field dependent magnetization data near the Curie temperature T[sub c] is devised, which allows the reliable determination of critical exponents even in strongly inhomogeneous ferromagnets. It is shown, both experimentally and theoretically, that the...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics