High-perveance sheet beam transport for MM-wave amplifiers

To develop compact, high-power, millimeter wave vacuum electronic amplifiers, it is important to minimize the operating voltage while increasing the operating current. Sheet electron beams are attractive for such amplifiers because if the current density can be maintained at round-beam levels, much higher beam current can be propagated in a sheet beam at a specified voltage. Although previous researchers have typically chosen periodic magnetic focusing for sheet beam transport, we have shown that solenoidal focusing can transport significantly higher current density beams over distances relevant to slow-wave or standing-wave amplifiers.