K. Tran Ngoc, P. T. Huy, N. D. Chien, C. Armellini, A. Chiasera, M. Ferrari, M. Montagna, C. G. Righini, “Effect of Yb³⁺ concentration on Er³⁺ luminescence properties of sol-gel-derived silica-alumina xerogels”, J. of Optoelectronic Materials, Vol. 2, No.5, 15 Sep 2006, 0354-0357

2.

G. Speranza, M. Ferrari, A. Chiasera, L. Calliari, A.M. Baranov, K. Tran Ngoc , V.V. Sleptsov, A. A. Nefedov, A.E. Varfolomeev and S.S. Franchenko "Er³⁺-doped thin amorphous carbon films prepared by mixed CVD sputtering”, Applied Surface Science, Vol. 238, Iss.1-4, 2004, 117-120.

3.

K. Tran Ngoc, P. T. Huy, N. D. Chien, M.Ferrari, A. Chiasera, C. Armellini, Y.Jestin, M. Montagna, G.C. Righini “Sol-gel derived Er³⁺/Yb³⁺ co-activated silica-alumina xerogels”, Proceeding of the first Vietnamese-Italian International Joint Workshop Photonics and Nano Technology, Hanoi, Nov. 28^th -29^th , 2005, p 111-120

4.

K.Tran Ngoc, P. T. Huy, N. D. Chien, M. Ferrari “Er³⁺/Yb³⁺ co-doped silica-alumina glasses: preparation and characterizations”, Proceeding of National Physics Conference VI, Hanoi, November, 2005, p 370 - 373.

5.

Maurizio Ferrari, Alessandro Martucci, Luca Zampedri, Cristina Armellini, Maurizio Montagna, Khiem Tran Ngoc , et al, “Erbium-activated sol-gel- Derived silica-hafnia planar waveguides”, Proceeding of the ICG in Kyoto, P-14-043, Sep. 27^th - Oct.1^st (2004).

6.

M. Ferrari, M. Montagna, A. Chiasera, K. Tran Ngoc, S. Pelli, G.C. Righini, et al, “Glass-based nanocomposite materials and confined structures for photonics”, Proceeding of the first Vietnamese-Italian International Joint Workshop Photonics and Nano Technology, Hanoi, November 28^th -29^th , 2005, p 71-79.

7.

T. T. An, P.T.Huy, K. Tran Ngoc, N.D. Chien, “Transparent conductive ZnO: Al thin films prepared by Sol-gel spin-coating”, Proceeding of the first Vietnamese-Italian International Joint Workshop Photonics and Nano Technology, Hanoi, November 28^th -29^th , 2005, p 101-104.

8.

M. Ferari, M. Montagna, C. Armellini, A. Chiasera, S. Pelli, G. C. Righini, E.Moser, Y. Jestin, A. Chiappini, K. Tran Ngoc, et al, “Optimizing Er³⁺- luminescent properties in photonic glasses: sensitizers, nano and micro-structures”, Proceeding of th MIPRO, Opatija, Croatia May 22 - 25 ,(2006), p 19-24.

9.

K. Tran Ngoc, P. T. Huy, N. D. Chien, M.Ferrari, G. C. Righini, et al, “Silica microspheres coated by Er³⁺-activated silica-hafnia sol-gel layers”, Proceeding of the International Conference Engineering Physics, October  9 -11, 2006, pp 30-34.

10.

M. Ferrari, M. Montagna, A. Chiasera, C. Armellini, K. Tran Ngoc, P. T. Huy, S. Pelli, G.C. Righini, E.Moser, et al, “Er³⁺- activated confined structure in photonic glasses”, Proceeding of the International Conference Engineering Physics, October  9 -11, 2006, pp 12-17.

11.

Tran Ngoc K., T. D. Trung, P.T. Huy, N.D. Chien, “Er³⁺ doped SiO₂-TiO₂-B₂O₃ planar waveguide: fabricating process and characterization”, Proceeding of the National solid state physics conference, Vung Tau, Viet Nam, 11-2007.

12.

N. D. Khoang, Tran Ngoc K, P.T. Huy, T. T. An, “Studying on structural and optical properties of the silica glass films doped with Er³⁺, Eu³⁺ and Yb³⁺”, Proceeding of the National solid state physics conference, Vung Tau, Viet Nam, 11-2007