title: Nested Helmholtz coil design for producing homogeneous transient rotating magnetic fields.
abstract: Electromagnets that can produce strong rotating magnetic fields at kHz frequencies are potentially very useful to exert rotating force on magnetic nanoparticles as small as few nanometers in size. In this article, the construction of a pulsed high-voltage rotating electromagnet is demonstrated based on a nested Helmholtz coil design. The energy for the coils is provided by two high-voltage discharge capacitors. The triggered spark gaps used in the experiments show sufficient accuracy to achieve the high frequency rotating magnetic field. The measured strength of the rotating magnetic field is 200 mT. This magnetic field is scalable by increasing the number of turns on the coils, by reducing the dimensions of the coils and by increasing the discharge current/voltage of the capacitors.
authors.affiliation: Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, USA.
authors.forename: George
authors.initials: G
authors.lastname: Podaru
authors.affiliation: Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, USA.
authors.forename: John
authors.initials: J
authors.lastname: Moore
authors.affiliation: Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, USA.
authors.forename: Raj Kumar
authors.initials: RK
authors.lastname: Dani
authors.affiliation: Department of Electrical and Computer Engineering, Kansas State University, Manhattan, Kansas 66506, USA.
authors.forename: Punit
authors.initials: P
authors.lastname: Prakash
authors.affiliation: Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, USA.
authors.forename: Viktor
authors.initials: V
authors.lastname: Chikan