We produced cylindrically imploded plasmas, which have the same density-radius product of the imploded plasma $\rho R$ with the compressed core in the fast ignition experiment and demonstrated efficient fast heating of cylindrically imploded plasmas with an ultraintense laser light. The coupling efficiency from the laser to the imploded column was 14%–21%, implying strong collimation of energetic electrons over a distance of $300\mu \mathrm{m}$ of the plasma. Particle-in-cell simulation shows confinement of the energetic electrons by self-generated magnetic and electrostatic fields excited along the imploded plasmas, and the efficient fast heating in the compressed region.

• Received 15 January 2008

DOI:https://doi.org/10.1103/PhysRevLett.100.165001