A method for producing a neutrons includes triggering a raising or a lowering of a temperature of a
pyroelectric crystal of less than about 40° C. to produce a
voltage of negative polarity of at least −100 keV on a surface of a deuterated or tritiated target coupled thereto. A
deuterium ion source is pulsed to produce a
deuterium ion beam. The accelerating of the
deuterium ion beam is achieved by accelerating
voltage of the
pyroelectric crystal toward the deuterated or tritiated target to produce neutrons. Furthermore, the
pyroelectric crystal, the deuterated or tritiated target, and the deuterium
ion source are coupled to a common support. The method also includes throwing the common support housing the pyroelectric
crystal, the deuterated or tritiated target, and the deuterium
ion source near an unknown
threat for identification thereof.