Magneto-optical Kerr effect studies of square artificial spin ice

We report a magneto-optical Kerr effect study of the collective magnetic response of artificial square spin ice, a lithographically-defined array of single-domain ferromagnetic islands. We find that the anisotropic inter-island interactions lead to a non-monotonic angular dependence of the array coercive field. Comparisons with micromagnetic simulations indicate that the two perpendicular sublattices exhibit distinct responses to island edge roughness, which clearly influence the magnetization reversal process. Furthermore, such comparisons demonstrate that disorder associated with roughness in the island edges plays a hitherto unrecognized but essential role in the collective behavior of these systems.

[1]  J. Cumings,et al.  Reducing disorder in artificial kagome ice. , 2011, Physical review letters.

[2]  J. Li,et al.  Ignoring your neighbors: moment correlations dominated by indirect or distant interactions in an ordered nanomagnet array. , 2011, Physical review letters.

[3]  R. Stamps,et al.  Diversity enabling equilibration: disorder and the ground state in artificial spin ice. , 2011, Physical review letters.

[4]  Olle Heinonen,et al.  Nanoscale structure of the magnetic induction at monopole defects in artificial spin-ice lattices , 2011 .

[5]  F Montaigne,et al.  Artificial kagome arrays of nanomagnets: a frozen dipolar spin ice. , 2011, Physical review letters.

[6]  T. Tyliszczak,et al.  Monopole defects and magnetic Coulomb blockade , 2011 .

[7]  V. Crespi,et al.  Comparing frustrated and unfrustrated clusters of single-domain ferromagnetic islands , 2010 .

[8]  V. Crespi,et al.  Comparing artificial frustrated magnets by tuning the symmetry of nanoscale permalloy arrays , 2010, 1003.1505.

[9]  J. Coey,et al.  Magnetism and Magnetic Materials , 2001 .

[10]  R. Moessner,et al.  Magnetic multipole analysis of kagome and artificial spin-ice dipolar arrays , 2009, 0906.3937.

[11]  V. Crespi,et al.  Tuning magnetic frustration of nanomagnets in triangular-lattice geometry , 2008, 0812.4468.

[12]  L. Heyderman,et al.  Building blocks of an artificial kagome spin ice : Photoemission electron microscopy of arrays of ferromagnetic islands , 2008 .

[13]  T. Lubensky,et al.  Geometric frustration in buckled colloidal monolayers , 2008, Nature.

[14]  A. Remhof,et al.  Magnetization reversal of microstructured kagome lattices , 2008 .

[15]  A. Remhof,et al.  Magnetostatic interactions on a square lattice , 2008 .

[16]  J. Cumings,et al.  Direct observation of the ice rule in an artificial kagome spin ice , 2008, 0802.0034.

[17]  R. Cava,et al.  Nonmonotonic zero-point entropy in diluted spin ice. , 2007, Physical review letters.

[18]  V. Rose,et al.  Demagnetization protocols for frustrated interacting nanomagnet arrays , 2007, cond-mat/0702084.

[19]  R. Moessner,et al.  Artificial square ice and related dipolar nanoarrays. , 2006, Physical review letters.

[20]  A. Libál,et al.  Realizing colloidal artificial ice on arrays of optical traps. , 2006, Physical review letters.

[21]  R. Cava,et al.  Zero-point entropy in stuffed spin-ice , 2006, cond-mat/0603146.

[22]  Eiji Saitoh,et al.  Magnetic interactions in a ferromagnetic honeycomb nanoscale network , 2006 .

[23]  V. Crespi,et al.  Artificial ‘spin ice’ in a geometrically frustrated lattice of nanoscale ferromagnetic islands , 2006, Nature.

[24]  R. Cowburn,et al.  Experimental study of the influence of edge roughness on magnetization switching in Permalloy nanostructures , 2004 .

[25]  R. Hertel,et al.  Micromagnetic study of magnetic configurations in submicron permalloy disks , 2003 .

[26]  C. Lacroix,et al.  Model of localized highly frustrated ferromagnetism: The kagomé spin ice , 2002 .

[27]  Ronald I. Smith,et al.  Magnetic properties of pure and diamagnetically doped jarosites: Model kagome antiferromagnets with variable coverage of the magnetic lattice , 2000 .

[28]  John Kerr Ll.D..  XLIII. On rotation of the plane of polarization by reflection from the pole of a magnet , 1877 .

[29]  R. Cowburn,et al.  Edge roughness and coercivity in magnetic nanostructures , 2005 .