Magnetic phase control by an electric field

Abstract

The quest for higher data density in information storage is motivating investigations into approaches for manipulating magnetization by means other than magnetic fields. This is evidenced by the recent boom in magnetoelectronics and 'spintronics', where phenomena such as carrier effects in magnetic semiconductors and high-correlation effects in colossal magnetoresistive compounds are studied for their device potential. The linear magnetoelectric effect-the induction of polarization by a magnetic field and of magnetization by an electric field-provides another route for linking magnetic and electric properties. It was recently discovered that composite materials and magnetic ferroelectrics exhibit magnetoelectric effects that exceed previously known effects by orders of magnitude, with the potential to trigger magnetic or electric phase transitions. Here we report a system whose magnetic phase can be controlled by an external electric field: ferromagnetic ordering in hexagonal HoMnO3 is reversibly switched on and off by the applied field via magnetoelectric interactions. We monitor this process using magneto-optical techniques and reveal its microscopic origin by neutron and X-ray diffraction. From our results, we identify basic requirements for other candidate materials to exhibit magnetoelectric phase control.

Magnetoelectric coupling at metal surfaces

“…The ultimate dream is to use MEC in magnetic data storage devices to write magnetic bits and to circumvent the issues summarized above as the magnetic recording trilemma. To date, MEC has mainly been observed in insulating materials such as complex multiferroic oxides where ferroelectric and ferromagnetic order parameters coexist [4,5,6]. The microscopic processes that lead to MEC in single-phase compounds are rather complex and still lack a complete theoretical understanding.…”

Elastic anomalies associated with structural and magnetic phase transitions in single crystal hexagonal YMnO3

“…Some of the most successful examples of magnetoelectric multiferroics have come from the hexagonal rare earth manganites, RMnO 3 , and significant research has been undertaken to understand the magnetic and ferroelectric properties of these compounds (see, for example, [1][2][3][4][5][6][7][8]). Of these materials YMnO 3 , with a layered structure with Y ions placed between sheets of corner sharing MnO 5 triangular bipyramids, has been of particular interest [9][10][11][12][13][14][15][16].…”

An investigation on magnetism, spin–phonon coupling, and ferroelectricity in multiferroic GdMn2O5

“…These materials are attractive due to the interesting physics involved and technologically important possibility for realizing the mutual controlling of electric and magnetic properties [2][3][4][5]. However, a number of multiferroics possess both ferroelectricity and magnetism but show a weak ME coupling [6].…”

“…However, a number of multiferroics possess both ferroelectricity and magnetism but show a weak ME coupling [6]. The recently revived multiferroics RMnO 3 [3,4,7,8] and RMn 2 O 5 [1,2,[9][10][11] (R = Y, Tb, Dy, etc.) exhibit remarkable ME effect and seem to be promising candidates for understanding the fascinating physics and pushing the potential applications of multiferroics.…”