Fig. 1. Emission patterns at the output of the crystal, recorded (a) at the very beginning of the experiment and after (b) 1 h and (c) 2.4 h of exposure time.

Fig. 2. Measured average powers of conical third, fifth, and seventh harmonics as functions of exposure time.

Fig. 3. Angle-resolved spectra of supercontinuum and harmonics emissions measured after (a) 3 min, (b) 1 h, and (c) 4 h of exposure time.

Fig. 4. Angle-integrated spectra of conical third (black curves), fifth (red curves), and seventh (blue curves) harmonics measured after (a) 1 h and (b) 4 h of exposure time.

Fig. 5. Time evolutions of angle-integrated (a) third-harmonic and (b) fifth-harmonic spectra.

Fig. 6. (a) Intensified image showing angular distribution of conical odd harmonics. Wave-vector diagrams for the generation of (b) third, (c) fifth, (d) seventh, and (e) ninth conical harmonics.

Fig. 7. Measured and calculated harmonics external cone angles (blue) and calculated nanograting periods (red).