  Boron carbonitride (BxCyNz) represents an interesting family of materials
containing all light elements and two dimensional graphene like hybrid layers.
Although rich literature exists on this peculiar material in chemically
processed form, there are relatively fewer reports on device application-worthy
thin film form. This form also offers a natural platform for basic studies on
important aspects such as magnetism and transport, which have attracted
attention in the context of ferromagnetism in doped and defect carbon systems.
Thus, in this work we have grown thin films of this compound using Pulsed Laser
Deposition (PLD) method, and investigated their magnetic and transport
properties in their entirety along with the detailed electronic structure using
various spectroscopic techniques like X-ray photoelectron spectroscopy (XPS),
Valence Band Spectroscopy (VBS) and X-ray absorption near edge spectroscopy
(XANES). In depth analysis of the typical role of dopants and defects,
especially the prevalent nitrogen defects, is elucidated using Density
Functional Theory (DFT) calculations to understand the experimental
observations. A dramatic crossover in the transport mechanism of charge
carriers is observed in this system with the change in doping level of specific
nitrogen defects. A robust and high saturation magnetization is achieved in BCN
films which is higher by almost hundred times as compared to that in similarly
grown undoped carbon film. An anomalous transition and increase in coercive
field is also observed at low temperature. A careful analysis brings out the
intriguing role of specific nitrogen defects in defining the peculiar nature
and concentration dependence of the physical properties of this system.
